In this article, a unified framework for multimodal search and retrieval is introduced. The framework is an outcome of the research that took place within the I-SEARCH European Project. The proposed system covers all aspects of a search and retrieval process, namely low-level descriptor extraction, indexing, query formulation, retrieval and visualisation of the search results. All I-SEARCH components advance the state of the art in the corresponding scientific fields. The I-SEARCH multimodal search engine is dynamically adapted to end-user’s devices, which can vary from a simple mobile phone to a high-performance PC.