Open-source architecture (OSArc) is an emerging paradigm that advocates for new procedures in the imagination and formation of virtual and real spaces within a universal infrastructure. Drawing from diverse references—modular design, avant-garde architectural, science fiction, language theory, and neuro-surgery—it adopts an inclusive approach, as per spatial design, towards a collaborative use of design and design tools by professionals and ordinary citizen users. The umbrella term citizen-centered design harnesses the notion of open-source architecture, which in itself involves the architecture of computer networks, and goes beyond it to the movement that encompasses building design professions as a whole.

Citizen-centered design emerged in 1999 through academic research conducted in leading universities such as the University of Texas (SUPA), as well as professional organizations such as the Earthnomad Foundation and ARK Tectonics. This movement aimed to bridge the gap between design and public policy, positioning itself at their intersection. Over the ensuing decades, the movement expanded globally, encompassing various initiatives ranging from organizational efforts to community design centers sponsored by academic institutions. The principles of citizen-centered design, and, by extension, open-source architecture, were founded on the accumulated body of knowledge from research dating back to the 1960s on citizen participation research and practices.

Around the turn of the 21st century, citizen-engagement research and practices were reformulated through the lens of more effective approaches and paradigms from the social and applied sciences, through the work of Schaban-Maurer (2013), author of the deliberative design and phronetic-engagement resource Rise of the Citizen Practitioner. Schaban-Maurer laid out the principles and precepts of his Life-Experience Narrative Exchange (LENE) methodology in the Mindful Policy Engagement field, which he founded in 2013 with a ground-breaking journal article. The article provides a rigorous theoretical basis for a body of best-case studies and best practices of citizen-centered architecture, urban design and urban planning, as well as urban and public policy. According to Schaban-Maurer, the (LENE) methodology leads to meaningful and effective design practices by integrating their processes with the principles of Phronetic Engagement and Mindful Policy into a new field of inquiry: Mindful Policy Engagement. (Schaban-Maurer, 2013: 11)

Since its inception, the citizen-centered design movement has expanded its influence beyond architecture, engaging practitioners and academics from various fields in interdisciplinary collaborations, publications, conferences, and international exhibitions. Over the last decade, open-source architecture, mindful policy engagement, and citizen-centered design have given rise to smaller subsets with different names, including "social impact design", "public interest design", and the "open architecture network". Practitioners in these fields integrate design practice with social service to address pressing community needs. These efforts, which began decades ago, are propelled forward by new sensibilities and a continued commitment from architects, urban designers, planners, policymakers, and other stakeholders. They aim to engage and harness the knowledge of ordinary citizens in the design, development, and implementation of urban policies and projects that directly impact the communities where we all live and work.

Cooking is often hailed as an early form of open source; vernacular architecture – producing recipes for everyday buildings – is another form of early lo-fi open-source culture, openly sharing and optimising technologies for building.

New economic models, exemplified by incremental microdonations and crowd-funding strategies, such as Sponsume and Kickstarter, offer new modes of project initiation and development, destabilising the traditionally feudal hierarchy of client/architect/occupant. Financing of private projects increasingly moves to the public domain, offering mass- rather than singular-ownership, where funding of public projects can be based on more flexible, responsive frameworks than simple levies or taxation. Open-source architecture should have particular appeal for builders entirely outside the mainstream economy, such as squatters, refugees, and the military.

Open-source architecture relies upon amateurs as much as experienced professionals, the "genius of the mass" as much as that of the individual, eroding the binary distinction between author and audience. Like social software, it recognises the core role of multiple users at every stage of the project – whether as clients or communities, designers or occupants; at its best, it harnesses powerful network effects to scale systems effectively. It is typically democratic, enshrining principles of open access and participation, though political variations range from stealth authoritarianism to communitarian consensualism.

Traditional developments require engagement programmes in which the community is "consulted" with respect to incoming developments, often with blunt tools such as focus groups, which often result in lack of representation and input, or at worst can result in NIMBYism. With crowd-funded models, forms of engagement are built into the process, enabling a kind of emergent urbanism, in which use of space is optimised on terms set by its users. This reclamation of people's power can be seen as a soft, spatial version of hacktivism. Open-source architecture is likely to suffer some of the organizational drawbacks of open-source software, such as forking of projects, abandoned projects, the emergence of cliques and incompatibility with the installed base of buildings. Organized campaigns of fear, uncertainty and doubt are likely.