**1. Introduction: Indonesia and sustainable development**

Human beings have an integral role in environmental management. However, we often cause damage to the environment by (ab)using natural resources and prioritizing developmentalism over maintaining balance with the natural world. This has contributed to climate change, rising sea levels, etc. Using sustainable designs, the negative environmental effects of construction can be reduced by relying on renewable resources, minimizing the environmental impact, and reuniting humanity with the natural world.

Indonesia is made up of islands with various ethnic communities with various local wisdoms, and various natural disasters that have occurred or will occur, including earthquakes, one of the frequent natural disasters. Response to natural disasters can be anticipated through consideration of the calculations and procedures for constructing buildings required for building standards (building code). The problem is nature as a place where we live is sometimes not used as a friend to be understood and followed by various things that are needed or demanded, but sometimes nature is regulated and made to follow human needs or interests. One way to get to know nature is to get to know the application of local wisdom that exists in a sustainable manner.

Behavioral and environmental architecture approach is a design approach that emphasizes the need to consider the quality environment that is lived by users and the impact on users of the environment, which forms the basis for considering the construction of houses and dwelling environments in Indonesia. The community believes that a design based on the concept of nature and opportunity can last a long time (sustainable). So traditional houses of each region in Indonesia have different shapes, forms, and characteristics following the conditions of the local natural environment.

The shape and form of buildings in several areas vary according to the characteristics of the location and the social system of the community so that the sustainability system in architecture can be understood from the "typical" building form of the area. This chapter will discuss the shape and form of buildings in Indonesia as part of sustainable architectural design. The interaction between form and shape is a longstanding source of discussion and debate in architecture. Scholars from Francis D.K. Ching and Rob Krier through Simon Unwin have shown that form and shape stimulate human imagination, emotions, and experiences [1, 2]. Despite producing different architectural sensations, however, the similar denotative meanings of form and shape have resulted in ambiguity in translation into Indonesian. As such, this chapter seeks to explore the concepts of form and shape using examples from the Indonesian Archipelago (also known as Nusantara), thereby providing a theoretical distinction based on geometrical elements. Particular emphasis will be given to a traditional form of architecture from Indonesia that will guide this book's attempts to Indonesianize the terms form.
