Veröffentlichungen von Dr. Nils Joachim

While many firms have introduced SOA, only one in five have achieved anticipated benefits such as increased IT flexibility or reuse. Industry analysts assume that a lack of SOA governance is the main reason why SOA projects fail. Addressing the substantial research gap on SOA governance this paper theoretically and empirically investigates which SOA governance mechanisms are needed to achieve the benefits of SOA, such as increasing IT flexibility and reusing services. The proposed theoretical SOA governance model is evaluated using data from 81 SOA-using organizations. Overall, the results confirm the relevance of a variety of SOA governance mechanisms (structures, processes, and employees/relations), but at the same time, that IT infrastructure flexibility and service reuse are influenced by different mechanisms. Key governance mechanisms that show a strong effect on infrastructure flexibility are using standards, service management processes, educating employees, and IT/business communication while reuse can only be increased through service management, standards and qualification. Contrary to expectations, implementing new, dedicated decision-making bodies for SOA hampers organizations in achieving higher degrees of IT flexibility and reuse, and a firm is better off using existing IT decision-making bodies.

How does a firm's IT architecture affect its potential to outsource business processes? As Information Technology (IT) has become many firms' essential operational infrastructure or "backbone", we are interested in scrutinizing to what extent the kind of IT architecture affects a firm's boundaries or the plasticity of its boundaries. Focusing on the particular concept of service-oriented architectures (SOA), we concretely ask: How does SOA affect business process outsourcing potentials? Since SOA is widely expected to modularize the IT implementation of business processes, it should increase business process outsourcing (BPO) in terms of buying in the provision of single business functionalities. We develop and empirically evaluate a theoretical model that conceptualizes the relationship between SOA and BPO. Questionnaire data from 115 firms give first evidence that SOA facilitates BPO. By increasing IT modularity, SOA supports BPO by increasing sourcing flexibility and, in particular, operational benefits, while at the same time lowering financial risks and strategic risks, such as lock-in. Overall, however, firms see SOA-based BPO mainly in an operational context with low hidden costs and little strategic benefits.

What is the interplay between Business Process Management (BPM) and Service-Oriented Architecture (SOA) in achieving high business process quality? In this paper, we empirically investigate the impact of both SOA and BPM on business process quality in terms of straight-through processing (STP), business-to-business integration, quality control, as well as standardization and consolidation of business processes. For the empirical evaluation of our model, we use the data of 157 German service firms. The results show that the SOA paradigm has still received rather low adoption rates in the industry. However, SOA, BPM, and related information technologies have a direct positive impact on business process quality and the analysis provides evidence for the complementarities of BPM and SOA since interaction effects between them have an additional significant impact on business process quality. Consequently, firms having adopted SOA can more effectively apply BPM.

Existing empirical research on the business value of Service-Oriented Architectures (SOA) has only measured the extent of SOA adoption - but not maturity - to determine whether typical goals, like increased business agility or IT cost reduction, could be achieved. However, a widely implemented SOA might be less mature than an SOA adopted only in particular areas of the organization, which in turn can lead to mismeasurement and misinterpretation. On the other side, the few existing SOA maturity frameworks that have been specified by previous researchers lack valid operationalizations to make them applicable to empirical research. Ready to use items and scales for evaluating the particular maturity level of an organization are missing. We propose to measure the degree of SOA maturity as a new variable for future empirical research especially in the context of SOA business value. Our analytical approach uses 21 items to classify the maturity of an organization's SOA in seven maturity levels along seven maturity dimensions derived from The Open Group Service Integration Maturity Model (OSIMM). The applicability of this new instrument is shown using data from 121 organizations. The results show that the majority of the organizations has only reached SOA maturity levels two to four. Also, higher levels of SOA maturity highly and significantly increase the realized business value from SOA in terms of business agility, straight through processing (STP), and reduced IT costs. However, the marginal benefits are decreasing for higher levels of SOA maturity in cases of STP and business agility.

By extending the research on identifying the possible benefits of Service-Oriented Architectures (SOA), we investigate how SOA delivers its value in an organization. One perspective in the existing literature suggests that service orientation works through creating better IT/Business collaboration as the "services" concept is a shared mental model that reduces the mental gap between IT and business units. Another perspective proposes that SOA benefits require IT/Business collaboration in the first place as IT and business must closely collaborate in order to leverage SOA's potential. We develop a theoretical model to understand how service orientation and close collaboration between IT and business departments are related. An analysis using data from 122 organizations reveals that SOA does not advance - but rather requires - close collaboration between the IT and business departments (i.e., collaboration is a moderator, not mediator, between SOA and its impacts). Therefore, close IT/business collaboration is an important success factor for realizing SOA's value potential and must be established using other means.

This literature review synthesizes existing research in the field of Service-Oriented Architectures (SOA) from a business perspective and integrates results from 40 works to offer researchers an overview about the existing body of knowledge in this research field as well as a research agenda, which unifies and extends previous efforts. While the literature regarding the technologies and design principles for SOA and even Service-Oriented Enterprises (SOE) converges, especially research regarding the identification of determinants influencing SOA adoption, governance mechanisms for effectively implementing SOA, and regarding SOA's actual business impact is needed. Previous empirical research indicated promising factors in each of these fields. However, future research should especially draw attention to holistically cover each of the research areas. Moreover, extending the use of empirical research methods will further improve our understanding regarding the importance of different adoption determinants, governance mechanisms, and the actual business value of SOA.

Sowohl die jüngere Forschung als auch die Erfahrung von Praktikern postulieren, dass eine SOA-Governance kritisch für eine erfolgreiche Implementierung von serviceorientierten Architekturen (SOA) ist. Dieser Beitrag bietet eine der ersten empirischen Untersuchungen bezüglich der Bedeutung verschiedener SOA-Governance-Mechanismen (Schaffung von Entscheidungsstrukturen, Nutzung von Standards, Verwendung von Servicemanagement- und Serviceentwicklungsprozessen, Qualifikation von Mit-arbeitern und Zusammenarbeit von Fachbereichen) für das Erreichen der gewünschten Modularität und einer hohen Wiederverwendungsrate. Die Ergebnisse basieren auf einer Umfrage unter deutschen Dienstleistungsunternehmen und zeigen, dass eine höhere Wiederverwendung nicht nur direkt durch verschiedene SOA-Governance-Mechanismen, sondern vor allem auch durch eine geeignetere Modularität als Mediator erreicht wird. Außerdem ist die Verwendung bestehender Entscheidungsstrukturen gegenüber der Schaffung neuer Entscheidungsstrukturen in Bezug auf die Erreichung von Modularität und Wiederverwendung zu favorisieren. Zuletzt wird ein starker Einfluss der Verwendung von Standards und klar definierter Servicemanagementprozesse auf die Effektivität von SOA deutlich.

Bisher wurde der Wertbeitrag der Nutzung von serviceorientierten Architekturen (SOA) für Unternehmen weder in der Praxis noch in der Forschung jenseits von Einzelfallbetrachtungen nachgewiesen. Wir untersuchen in einer ersten quantitativen Studie die realisierten Vorteile einer SOA-Nutzung im Hinblick auf Kostenreduktion, unternehmerische Agilität, Datenqualität, Prozess-Monitoring, interne Geschäftsprozessintegration (STP) und unternehmensübergreifende Integration (B2B). Die Analyse von 134 Unternehmensantworten zeigt, dass SOA zu allen sechs Unternehmensvorteilen beiträgt. Außerdem ist erkennbar, dass sich SOA in klassischen Aspekten flexibler IT-Infrastrukturen wie Modularität, Flexibilität und Skalierbarkeit widerspiegelt. Und auch die Realisierung von Unternehmensvorteilen durch SOA kann zu bedeutenden Teilen über die Verbesserung der IT-Flexibilität als Mediator erklärt werden.

Diese Arbeit untersucht die Auswirkung von operativem ITBusiness-Alignment sowie insbesondere der Gestaltung der Beziehungsschnittstelle zwischen verschiedenen Fachbereichen auf die Nutzungsintensität von Informationssystemen sowie auf die Geschäftsprozessleistung. Wir entwickeln ein theoretisches Modell unter Anwendung einer sozialen Perspektive auf Alignment und auf die Beziehungsschnittstelle und evaluieren es anhand einer Studie der IT-Nutzung im Firmenkreditprozess US-amerikanischer Banken. Die Ergebnisse zeigen, dass die Qualität der Beziehungsschnittstelle zwischen verschiedenen Fachbereichen einerseits und zwischen IT-Einheit und Fachbereichen (gemessen in Form von Vertrauen, gemeinsames Wissen und struktureller Interaktion) andererseits erhebliche Auswirkungen auf die Nutzung der Informationssysteme im Kreditprozess und darüber auf die Leistung des Kreditprozesses haben. Insbesondere der Zusammenhang im Dreieck operatives Alignment, Beziehungsschnittstelle zwischen Fachbereichen und Nutzung von Informationssystemen liefert einen neuen Beitrag zu unserem Verständnis des Geschäftswertbeitrages der IT.

Recent research results and practitioner experience both posit that Service-Oriented Architecture (SOA) governance is critical to successfully implement and utilize SOA. We investigate the impact of different SOA governance and management mechanisms (structures, processes, and employees) for leveraging SOA's potential to increase an organization's IT infrastructure flexibility. The results based on data from 73 SOA using organizations reveal: (1) a negative impact of implementing new decision-making bodies on 2 dimensions of IT flexibility (IT modularity and integration) (2) a positive impact of the SOA management processes service management and service development on 2 dimensions of IT flexibility (modularity and integration of IT infrastructure) (3) a positive impact of business units collaboratively identifying jointly utilizable services on modularity (4) and a particularly strong impact of standards, and also of employee qualification, on all dimensions of IT infrastructure flexibility.

What are the determinants of an organization's decision to adopt Service-Oriented Architecture (SOA)? Although the paradigms of service orientation and SOA have become quite omnipresent in the IS literature, research is still lacking to provide a comprehensive view upon drivers and inhibitors of the organizational decision to adopt SOA. Based on the mature strand of adoption research, this paper develops a conceptual model in order to increase the understanding of the determinants influencing this decision. Thereby, the drivers and inhibitors are distinguished in organization-specific and innovation-specific factors. The organization-specific factors cover two aspects: (1) the compatibility of technology and organization (i.e., SOA expertise of the employees, management support for SOA, IT/ Business alignment, degree of process documentation) and (2) management fad and fashion. The innovation-specific factors cover the perceived benefits, perceived complexity, and standardization of available technologies related to SOA. Beside developing this theoretical model for laying the foundation for future empirical research, a further contribution of this paper is the development of a comprehensive measurement model for SOA adoption, which differentiates between the IT and the enterprise layer.

How does the availability of an SOA within a firm affect the potential of and intention for outsourcing business activities? Since one of the promises of SOA is to modularize the IT representation of business processes, it should facilitate business process outsourcing in terms of buying the provision of single business functionalities. In this paper, we develop a conceptual research model that theorizes the relationship between SOA and BPO intention.

This research investigates the economic benefits which Service-Oriented Architectures (SOA) promise. While more and more organizations adopt SOA, virtually none of them is able to predict the realizable business value of SOA ex ante. In contrast to the mature literature on the technological aspects of SOA, the organizational impacts of SOA are not explored in detail in the academic literature yet. Consequently, this proposal addresses two problems identified in current SOA research: First, a SOA adoption model is developed to evaluate the determinants of an organization's decision to adopt SOA. Second, a research model for enhancing the understanding of SOA's business value is developed. The first part of the proposal will draw on the technology-organization-environment (TOE) framework in order to increase the knowledge about the dissimilar impacts of different determinants which influence an organization's decision concerning the adoption of SOA. To address the second part of this research proposal, the model regarding the business value of SOA is based on the dynamic capabilities theory. Comparing organizations, which have adopted SOA with varying degree with others which have not adopted SOA at all, allows to determine the realistic economic impacts of SOA on an organization. Moreover, the business value model further investigates IT flexibility and IT business alignment as promising mediating factors which support the actual realization of SOA's potential business value.

What is the interplay between IT/Business alignment and Service-oriented Architecture (SOA) regarding the achievement of business value in terms of business flexibility? This paper introduces a conceptual model that derives propositions about how IT/Business alignment, IT flexibility, and business flexibility are interrelated and how SOA and alignment interact in order to increase business flexibility. We apply and integrate well-known multi-dimensional concepts of both IT/Business alignment (in terms of strategic alignment, structural alignment, and social alignment) and IT flexibility (technical and non-technical IT flexibility) and map the conceptual components of SOA (architectural and the governance dimension) to this resulting model. This conceptualization will allow for more profoundly structured research on how SOA contributes to business value.

This paper argues that business process standardization, as part of BPM activities, is an effective way to improve business process flexibility and performance. We develop and empirically evaluate a theoretical model of the differential impact of business process homogenization and optimization on business process flexibility and performance. The analysis based on data from 85 large firms shows a strong and highly significant influence of process standardization on business process flexibility and performance. This paper is among the first to propose a research model and empirical operationalization to analyze the twofold impact of process standardization on business process flexibility and performance. For practitioners the paper provides actionable recommendations on how to apply the findings to their management context.

What is the impact of a Service-oriented Architecture (SOA) on the efficiency and effectiveness of business process standardization (BPS)? The contribution of this paper is the development of a research model around the impact of SOA on BPS in terms of achieving fundamental efficiency and flexibility potentials while covering both the business layer and the IT layer of the firm. Drawing on an accepted and widespread enterprise architecture model, we derive propositions that explain why and how SOA's characteristics help to standardize business processes and how the interplay between SOA and BPS leads to an increased overall business value. Additional moderator arguments, such as the level of service granularity, the centrality of SOA governance, or Business IT alignment, are added to the research model as critical success factors of achieving business value of SOA.

We empirically investigate the interplay and impact of process standardization and IT intensity on business process performance in terms of efficiency, quality, control, and processing time. To this aim we surveyed the retail advisory operations of Germany's largest banks. We find that standardization enhances efficiency, quality and control of the advisory process. Additionally, IT intensity on its own shows positive effects on efficiency and quality as well, while it leads to more customer facing time needed for a single customer. Also, the interaction effect with process standardization is relevant. We conclude that IT creates business value through facilitating process standardization and process control. Our results strongly indicate that managers have to look carefully at the type of the processes before standardizing it.

Our research intends to explore whether a social perspective on IT business alignment can help shed light on the IT value creation process by considering different facets of interpersonal linkage. In this paper, we develop a theoretical model which could be discussed at the JAIS workshop. Further, we use some empirical data from 149 US banks in order to find first empirical evidence whether our research focus represents a promising direction. We find initial support for our main hypotheses that communication, cross-domain knowledge and mutuality among and between IT and business staff significantly impact IT usage and business process outcomes. The final results of our research could contribute to our understanding of how the IT resource should be understood and used to measurably contribute to firm goals. The initial findings support the caveat of recent studies suggesting that informal aspects of alignment might be quite notable (e.g. Chan, 2002) and show that our theoretical understanding of alignment should be extended to better incorporate social aspects of daily work life.

What is the business value of Service-Oriented Architectures (SOA) and how can we achieve it? This paper represents a conceptual piece of research which focuses on the impact of IT Business Alignment (ITBA) on the successful implementation of SOA, in terms of its business value. The contribution of this model is predominant in proposing a threefold effect of ITBA on achieving a successful implementation of SOA through the specific strategic needs defined by a particular firm in a specific industry, i.e., the banking industry. As a result, we show that the business strategy moderates the impact of SOA‟s general potentials on its actual business value and claim that this relationship is further moderated by ITBA, which must be thoroughly considered by practitioners deciding on introducing SOA in their firm.

Although many firms have started or accomplished to migrate their IT infrastructure towards a ser-vice-oriented architecture (SOA), as flexible and adaptive fundament of their business applications, there is still a gap answering one of the most essential questions associated with this new architecture para-digm: What is the business value of SOA and how can we influence it?

What is the business value of Service Oriented Architecture? Although the SOA paradigm has become quite evident in IS literature, a comprehensive model of the SOA business value is still lacking. Based on a literature review and on a multitheoretical foundation, drawing on the adoption of innovations literature and on the resource-based view as well as on resource dependency theory, we attempt to develop a research model which captures the business value of SOA, applicable to empirical research in subsequent studies.

This paper presents a framework assisting managers in their decision making about introducing a service-oriented architecture (SOA). The benefits, risks and efforts associated with SOA are discussed from a business value perspective. The paper contributes to the literature by suggesting a unified foundation for the debate on the business value of SOA by proposing concrete value drivers and their interrelations.

How does the availability of an SOA within a firm affect the potential of and intention for outsourcing business activities? Since one of the promises of SOA is to modularize the IT representation of business processes, it should facilitate business process outsourcing in terms of buying the provision of single business functionalities. In this paper, we develop a conceptual research model that theorizes the relationship between SOA and BPO intention.

What is the business value of Service-Oriented Architectures (SOA) and how can we achieve it? This paper represents a conceptual piece of research which focuses on the impact of IT Business Alignment (ITBA) on the successful implementation of SOA, in terms of its business value. The contribution of this model is predominant in proposing a threefold effect of ITBA on achieving a successful implementation of SOA through the specific strategic needs defined by a particular firm in a specific industry, i.e., the banking industry. As a result, we show that the business strategy moderates the impact of SOA's general potentials on its actual business value and claim that this relationship is further moderated by ITBA, which must be thoroughly considered by practitioners deciding on introducing SOA in their firm.

Since the first introduction of the term Service-Oriented Architecture (SOA) by Gartner analysts in 1996, the idea of service orientation of IS architectures including SOA and its supporting technologies has become a widely adopted concept both in industry and research. SOA leverages the principles of object-oriented and component-oriented programming not only for the development of single systems but for entire system landscapes by adding a new service layer consisting of loosely coupled modular services. In recent years, a number of definitions for SOA appeared that varied with respect to their scope. Researchers applied the concept of service orientation not only for designing business application systems (i.e., a narrow scope of SOA), but also for designing the business architecture and so introduced the concept of a "Service-Oriented Enterprise (SOE)". Early SOA research focused on technical aspects regarding the characteristics of SOA. However, while providing a solid technological base for implementing SOA, the business perspective on SOA has been largely neglected and gained increasing attention in recent years. Even though recent research has already increased the understanding of SOA from a business perspective, researchers struggle to provide theoretical foundations as well as to apply quantitative empirical research to investigate the relationships on a larger empirical basis. The cumulative dissertation thesis at hand addresses these areas by drawing on a multi-theoretical foundation and applying a multi-method approach in order to address the following research directions: Adoption: Why and under what circumstances do organizations introduce SOA? Business impact: What are the benefits resulting from SOA? Governance: How should SOA introduction and management be governed to achieve the benefits? These research directions are targeted by the eight research articles included in this dissertation thesis following a quantitative approach. First, the foundation for the thesis is laid by reviewing the literature and identifying research questions. Next, nine case studies were conducted to understand SOA adoption, its implications for the organization as well as the used governance mechanisms in depth, and to refine the research models based on further insights from practice. Third, necessary prerequisites for applying quantitative methods are developed in terms of conceptualizing SOA adoption and developing measurement instruments for SOA adoption and SOA maturity based on their characteristics. Based on this preliminary work the developed research models that draw on different theoretical foundations - e.g., modular systems theory, dynamic capabilities theory (DCT), or the technology-organization-environment (TOE) framework - were tested using quantitative methods. Besides different theoretical foundations, the individual papers leverage different statistical analyses, such as structural equation modeling (SEM), factor analysis, or cluster analysis. For our quantitative analyses, we used the data of 247 participating organizations collected through a survey carried out in the German service industry. The results of the analyses are documented in eight research articles that are partly published and partly under review at international journals. Five different approaches to SOA adoption are identified: no SOA adoption, service-oriented business architecture, medium extent among all four SOA dimensions, medium extent with high service orientation of IS architecture, and high extent among all four SOA dimensions. SOA adoption is based predominantly on organizational prerequisites such as IT employees' IT expertise, top management support, and the compatibility of SOA with an organization's IT setting. Further determinants are relative advantage, costs, and organization size. Notably, the complexity of implementing SOA is seen as a cost driver but not as an inhibitor. The results show that an organization's SOA adoption is also influenced by observable SOA adoption from other firms ("same group", i.e., management fad) and from media, consultants and other sources ("outside group", i.e., management fashion). This thesis offers a theoretical and empirical explanation for SOA's business impact. The results substantiate the oft-proclaimed business value discussion of SOA by showing quantitatively significant relationships between the degree of SOA and business-relevant value dimensions in terms of reducing costs and increasing business agility, data quality, process monitoring, internal straight-through processing (STP), and business-to-business (B2B) integration of processes. Also, we offer a theoretical foundation by drawing on the concept of dynamic capabilities to argue theoretically and to show empirically that IT flexibility is a meaningful explanatory factor for SOA's business value. Further, the results show a diminishing marginal utility of increasing SOA maturity. In addition, this is the first study that conceptualizes and empirically evaluates a measurement instrument for business process management (BPM) and offers first insights into how BPM and SOA jointly affect business process quality. Moreover, SOA is identified to be a good foundation for business process outsourcing (BPO) as it increases related benefits and flexibility while reducing associated risks. This thesis offers an evidence-based contribution to the discussion of the role of SOA governance mechanisms and a validated measurement model that is useful when bringing together managerial and technical perspectives regarding service orientation. Notably, establishing new SOA decision-making bodies, such as the often called for SOA centers of excellence (CoE), hampers modularity, integration and reuse in the beginning. Thus, one important managerial result is that organizations do not necessarily need to implement new decision-making bodies but should prefer adapting existing ones. Among others, standards, employee qualification, and IT/business communication are important for these purposes. Managers pursuing better IT scalability are also well advised to follow this recommendation, as these three mechanisms (but only these of the investigated) also drive scalability. For improving modularity, clear service development processes and the collaborative work of business units are applicable governance mechanisms. Further, the findings suggest that managers should not hope for better alignment automatically following the SOA implementation, but instead explicitly implement management actions that facilitate collaboration between business and IT as this further improves the outcomes of implementing SOA. Answering these research questions contributes to theory in multiple ways by offering theoretical and empirical explanations for the determinants of SOA adoption, governance mechanisms, and SOA's business impact, as well as providing a newly developed multidimensional SOA research concept and a measurement instrument for SOA maturity. Moreover, answering these research questions also contributes to a topic of high practical relevance. According to Forrester Research, 84% of the global 2,000 enterprises (i.e., organizations with 20,000 or more employees) use SOA. Despite the high rate of SOA adoption among very large organizations the same study shows that only 12 percent of the global 2,000 enterprises achieve the intended SOA benefits. Thus, insights into questions surrounding important adoption determinants for implementing SOA, SOA's realistic potential business impact, and effective SOA governance mechanisms are of particular importance for managers, especially given that typically there is a high cost associated with introducing SOA.