Heparan sulphate proteoglycans (HSPGs) are widely distributed in animal tissues, but their most prominent locations are cell surface membranes and basement membranes. Their influence on various fundamental aspects of cell behaviour (e.g. cell adhesion, growth and morphogenesis) are dependent on the specific binding properties of the heparan sulphate (HS) chains. These polysaccharides are complex structures in which N-sulphated glucosamine and ester sulphate groups tend to be clustered in discrete regions of the chain separated by sequences enriched in N-acetylglucosamine residues, but with a low sulphate concentration. The sulphated domains contain the sugar residue sequences for interaction with specific proteins essential for HS function. In this review, we describe the plasma membrane HSPGs and their role in regulating the activity of basic fibroblast growth factor (bFGF).