In the recent years studies based on two-hybrid screens, proteomic, biochemical and cell biology approaches, have shown that intracellular domains of G protein-coupled receptors (GPCR) or heptaspanning membrane receptors (HSMRs) interact with intracellular proteins. These interactions are the basis of a protein network associated to these receptors which includes scaffolding proteins containing one or several PDZ (post-synaptic density-95, discs large, zona occludens-1) domains, signalling proteins and proteins of the cytoskeleton. The present book is focused on the emerging evidence for interactions of G protein-coupled receptors with scaffolding, cytoskeletal and signalling proteins that will play a role in the targeting, anchoring and functioning of these receptors in the plasma membrane, thus contributing to cell development and plasticity.