Indispensable features of complementary architecture include sustainability, altruism, contextualism, endemism and continuity of specific regional design language.
A pattern language represents a set of more or less formalised rules of human interaction with built forms, resulting from practical solutions developed over time according to local culture and natural conditions.
[3] Complementary architecture interprets the Vitruvian triad for contemporary use, mapping durability (firmitas) against aspects of broader sustainability, utility (utilitas) against altruism and service to society, and individual beauty (venustas) against harmony with broader context, regional identity and spirit of place.
[6] Complementary architecture involves systematic analysis of traditional techniques in the context of vibrant urban environments, aiming to rediscover sustainable, layered, nuanced, contextual and environmentally appropriate solutions for the present time.
[10][11] Adherents posit that in the 20th century the abdication of decorative elements and traditional forms was thought to be a sign of newly found simplicity, solidarity and sacrifice by the socialist and conveniently cost-efficient by the capitalist side of the political scene.