The multidomain extracellular protein fibronectin (Fn) is assuming an increasingly important role in cell biology. Interactions between Fn and juxtaposed cells play an important role in the regulation of cell migration, adhesion, growth, differentiation and apoptosis. This classical outside-in signalling leads to the activation of intra-cellular signalling pathways and results in the transient formation of protein-protein complexes and alterations in the states of protein phosphorylation which ultimately lead to changes in gene expression. The role of Fn in the aetiology and regulation of different disease processes is an increasingly popular research area. The role of Fn in the establishment and spread of tumour cells is one such topic. This book draws on the expertise of many laboratories to provide up to date research findings for those interested in this field.