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ISAM is a proposal directed to supporting physical and logical mobility, context-awareness, dynamic adaptation and the execution of large-scale distributed applications. In order to achieve its goals, ISAM uses, as strategy, an integrated environment that provides: (a) a programming language; (b) an execution environment; (c) a context recognition server. The integration is accomplished through an adaptation process that uses a multilevel collaborative model, in which both the system and the application contribute for that. In this paper we discuss the main components used to implement the ISAM features, and we also present a distributed application that explores some of this features.

The concept of pervasiveness provides the future of computing with an attractive perspective. However, software support for physical and logical mobility raises a set of new requirements and challenges for software production, creating demand for new types of applications, the so‐called pervasive applications, which express follow‐me semantics. The core of these challenges is a dynamic operating environment, which originates with the users' movement in different terminals and locations, and determines different execution contexts. For this envision to become a reality, developers must build applications that constantly adapt to a highly dynamic computing environment. Research works in pervasive computing have already addressed important issues, but they do not approach the problem of how to program general‐purpose pervasive systems. Pervasive applications are distributed, mobile, adaptive and consider context as a first‐order concept. To make the developers' task easier, we have introduced the software architecture called ISAM, which provides an integrated environment aimed at building pervasive applications composed of a development environment and an execution middleware. As part of our study within the ISAM project, we have been investigating how context‐awareness can be expressed at the programming language level with a basis on four main abstractions: context, adapters, adaptation commands, and adaptive behavior management policies. This paper introduces such abstractions, and presents some development and management tools anchored on an example application, which is under development. Copyright © 2006 John Wiley & Sons, Ltd.