Enterprise architecture (EA) is an analytical discipline that provides methods to comprehensively define, organize, standardize, and document an organization’s structure and interrelationships in terms of certain critical business domains (physical, organizational, technical, etc.) characterizing the entity under analysis. The goal of EA is to create an effective representation of the business enterprise that may be used at all levels of stewardship to guide, optimize, and transform the business as it responds to real-world conditions. EA serves to capture the relationships and interactions between domain elements as described by their processes, functions, applications, events, data, and employed technologies. 
As practitioners of enterprise architecture, enterprise architects support an organization’s strategic vision by acting to align people, process and technology decisions with actionable goals and objectives that result in quantifiable improvements toward achieving that vision. The practice of enterprise architecture:
analyzes areas of common activity within or between organizations, where information and other resources are exchanged to guide future states from an integrated viewpoint of strategy, business, and technology.
Enterprise architecture (EA) is a discipline for proactively and holistically leading enterprise responses to disruptive forces by identifying and analyzing the execution of change toward desired business vision and outcomes. EA delivers value by presenting business and IT leaders with signature-ready recommendations for adjusting policies and projects to achieve target business outcomes that capitalize on relevant business disruptions. EA is used to steer decision making toward the evolution of the future state architecture.
It helps business and IT managers to figure out the best strategies to support and enable business development and business change – in relation to the business information systems that the business depends on.
In that sense, the term enterprise covers various types of organizations, regardless of their size, ownership model, operational model, or geographical distribution. It includes those organizations' complete socio-technical systems, including people, information, processes, and technologies.
The term architecture refers to fundamental concepts or properties of a system in its environment, embodied in its elements, relationships, and in the principles of its design and evolution.
Understood as a socio-technical system, the term enterprise defines the scope of the enterprise architecture.
Perspectives, or beliefs, held by enterprise architecture practitioners and scholars, with regards to the meaning of the enterprise architecture, typically gravitate towards one or a hybrid of three schools of thought:
Enterprise IT design – the purpose of EA is the greater alignment between IT and business concerns. The main purpose of enterprise architecture is to guide the process of planning and designing the IT/IS capabilities of an enterprise in order to meet desired organizational objectives. Typically, architecture proposals and decisions are limited to the IT/IS aspects of the enterprise; other aspects only serve as inputs.
Enterprise integrating – According to this school of thought, the purpose of EA is to achieve greater coherency between the various concerns of an enterprise (HR, IT, Operations, etc.) including the linking between strategy formulation and execution. Typically, architecture proposals and decisions encompass all the aspects of the enterprise.
Enterprise ecosystem adaptation – the purpose of EA is to foster and maintain the learning capabilities of enterprises so that they may be sustainable. Consequently, a great deal of emphasis is put on improving the capabilities of the enterprise to improve itself, to innovate and to coevolve with its environment. Typically, proposals and decisions encompass both the enterprise and its environment.
One’s belief with regards to the meaning of enterprise architecture will impact how one sees its purpose, its scope, the means of achieving it, the skills needed to conduct it, and the locus of responsibility for conducting it
According to the standard ISO/IEC/IEEE 42010, the product used to describe the architecture of a system is called an architectural description. In practice, an architectural description contains a variety of lists, tables, and diagrams. These are models known as views. In the case of enterprise architecture, these models describe the logical business functions or capabilities, business processes, human roles and actors, the physical organization structure, data flows and data stores, business applications and platform applications, hardware, and communications infrastructure.
The UK National Computing Centre EA best practice guidance states:
Normally an EA takes the form of a comprehensive set of cohesive models that describe the structure and functions of an enterprise. The individual models in an EA are arranged in a logical manner that provides an ever-increasing level of detail about the enterprise.
The architecture of an enterprise is described with a view to improving the manageability, effectiveness, efficiency, or agility of the business, and ensuring that money spent on information technology (IT) is justified.
Paramount to changing the enterprise architecture is the identification of a sponsor. His/her mission, vision, and strategy, and the governance framework define all roles, responsibilities, and relationships involved in the anticipated transformation. Changes considered by enterprise architects typically include:
innovations in the structure or processes of an organization
innovations in the use of information systems or technologies
improving the quality and timeliness of business information.
A methodology for developing and using architecture to guide the transformation of a business from a baseline state to a target state, sometimes through several transition states, is usually known as an enterprise architecture framework. A framework provides a structured collection of processes, techniques, artifact descriptions, reference models, and guidance for the production and use of an enterprise-specific architecture description.
The benefits of enterprise architecture are achieved through its direct and indirect contributions to organizational goals. It has been found that the most notable benefits of enterprise architecture can be observed in the following areas:
Organizational design – Enterprise architecture provides support in the areas related to design and re-design of the organizational structures during mergers, acquisitions or during general organizational change.
Organizational processes and process standards – Enterprise architecture helps enforce discipline and standardization of business processes, and enable process consolidation, reuse, and integration.
Project management – Enterprise architecture enhances the collaboration and communication between project stakeholders. Enterprise architecture contributes to efficient project scoping and to defining more complete and consistent project deliverables.
Requirements engineering – Enterprise architecture increases the speed of requirement elicitation and the accuracy of requirement definitions, through publishing of the enterprise architecture documentation.
System development - Enterprise architecture contributes to optimal system designs and efficient resource allocation during system development and testing.
IT management and decision making – Enterprise architecture is found to help enforce discipline and standardization of IT planning activities and to contribute to a reduction in time for technology-related decision making.
IT value – Enterprise architecture helps reduce the system's implementation and operational costs, and minimize replication of IT infrastructure services across business units.
IT complexity – Enterprise architecture contributes to a reduction in IT complexity, consolidation of data and applications, and to better interoperability of the systems.
IT openness – Enterprise architecture contributes to more open and responsive IT as reflected through increased accessibility of data for regulatory compliance, and increased transparency of infrastructure changes.
IT risk management – Enterprise architecture contributes to the reduction of business risks from system failures and security breaches. Enterprise architecture helps reduce risks of project delivery.
For various understandable reasons, commercial organizations rarely publish substantial enterprise architecture descriptions. However, government agencies have begun to publish architectural descriptions they have developed. Examples include:
An Enterprise Architecture practice collaborates with many interconnected disciplines, including performance engineering and management, process engineering and management, IT and enterprise portfolio management, governance and compliance, IT strategic planning, risk analysis, information management, metadata management, and a wide variety of technical disciplines as well as organizational disciplines such as organizational development, transformation, innovation, and learning. Increasingly, many practitioners have stressed the important relationship of Enterprise Architecture with emerging holistic design practices such as design thinking, systems thinking, and user experience design.
Discussions of the intersection of enterprise architecture and various IT practices have been published by various IT analysis firms. Gartner and Forrester have stressed the important relationship of enterprise architecture with emerging holistic design practices such as Design Thinking and User Experience Design. Analyst firm Real Story Group suggested that enterprise architecture and the emerging concept of the digital workplace were "two sides to the same coin." The Cutter Consortium describes enterprise architecture as an information and knowledge-based discipline.
The enterprise architecture of an organization is too complex and extensive to document in its entirety, so knowledge management techniques provide a way to explore and analyze these hidden, tacit, or implicit areas. In return, enterprise architecture provides a way of documenting the components of an organization and their interaction, in a systemic and holistic way that complements knowledge management.
In various venues, enterprise architecture has been discussed as having a relationship with Service Oriented Architecture, a particular style of application integration. Research points to enterprise architecture promoting the use of SOA as an enterprise-wide integration pattern.
Establishing enterprise architecture, as accepted, recognized, functionally integrated and fully involved concept at operational and tactical levels is identified as one of the biggest challenges facing Enterprise Architects today and one of the main reasons why many EA-Initiatives fail.
Despite the benefits that enterprise architecture claims to provide, for more than a decade, writers and organizations raised concerns about enterprise architecture as an effective practice. Here is a partial list of those objections:
In 2007, computer scientist Ivar Jacobson (a major contributor to UML and pioneer in OO software development) gave his assessment of enterprise architecture: "Around the world introducing an Enterprise Architecture EA has been an initiative for most financial institutions (banks, insurance companies, government, etc.) for the last five years or so, and it is not over. I have been working with such companies and helped some of them to avoid making the worst mistakes. Most EA initiatives failed. My guess is that more than 90% never really resulted in anything useful."
In a 2007 report, on enterprise architecture, Gartner predicted that "... by 2012 40% of [2007’s] enterprise architecture programs will be stopped."
A 2008 study performed by Erasmus University Rotterdam and software company IDS Scheer concluded that two-thirds of enterprise architecture projects failed to improve business and IT alignment.
In a 2009 article, industry commentator Dion Hinchcliffe wrote that traditional enterprise architecture might be "broken": "At its very best, enterprise architecture provides the bright lines that articulate the full range of possibilities for a business, even describing how to go about getting there. ... Recently there’s a growing realization that traditional enterprise architecture as it’s often practiced today might be broken in some important way. What might be wrong and how to fix it are the questions du jour."
In 2011, federal enterprise architecture consultant Stanley Gaver released a report that examined problems within the United States federal government’s enterprise architecture program. Mr. Gaver concluded that the federal enterprise architecture program had mostly failed; this conclusion was corroborated by a similar one made by the federal government at an October 2010 meeting that was held to determine why the federal enterprise architecture program was not "as influential and successful as in the past."
A key concern about EA has been the difficulty in arriving at metrics of success, because of the broad-brush and often opaque nature of EA projects.
^ abLapalme, J., Three Schools of Thought on Enterprise Architecture, IT Professional, vol. 14, no. 6, pp. 37–43, Nov.–Dec. 2012, doi:10.1109/MITP.2011.109
^Jarvis, Bob (2003) Enterprise Architecture: Understanding the Bigger Picture – A Best Practice Guide for Decision Makers in IT, The UK National Computing Centre, Manchester, UK. p. 9
^The Contribution of Enterprise Architecture to the Achievement of Organizational Goals: Establishing the Enterprise Architecture Benefits Framework, Technical Report, Department of Information and Computing Sciences Utrecht University, Utrecht, The Netherlands, (2010 online)
^Bert Arnold, Martin Op 't Land and Jan Dietz. "Effects of an architectural approach to the implementation of shared service centers," in Second International Workshop on Enterprise, Applications and Services in the Finance Industry (FinanceCom05), Regensburg, Germany, 2005.
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^M. Pulkkinen, A. Naumenko and K. Luostarinen, "Managing information security in a business network of machinery maintenance services business - Enterprise architecture as a coordination tool," J. Syst. Softw., vol. 80, pp. 1607-1620, 2007.
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^Dedic, N. (2020). "FEAMI: A Methodology to include and to integrate Enterprise Architecture Processes into Existing Organizational Processes" in IEEE Engineering Management Review. Volume 48, Issue 4. DOI: https://doi.org/10.1109/EMR.2020.3031968