This study involved the isolation and purification of collagen peptides and a characterisation of the effects of these peptides on cell behaviour. In vitro experiments were carried out on CNBr-derived peptides from collagens I and III, and these were shown to stimulate fibroblast growth and chemotaxis. Peptides CB3 and CB8 from collagen a1(I) and peptides CB4 and CB8 from collagen aI(III) showed the most potent stimulation. A chemotactic peptide, 22 amino acids in length, obtained by sequential enzymatic digestion of collagen I with bacterial collagenase and chymotrypsin was isolated and this peptide was also found to be a potent chemoattractant for fibroblasts. A tetra-peptide with the amino acid sequence Gly-Pro-Ala-Gly was identified as one of the most chemotactically active regions in the collagen molecule. The collagen peptide (22 amino acid sequence) was also tested in vivo for its ability to stimulate cellular infiltration and granulation tissue formation using the PVA (polyvinyl alcohol) model system in rats. The peptide was injected into PCVA sponges which had been implanted into rats. After 7 or 10 days the sponges were removed and analysed both histologically and biochemically. The levels of collagen, DNA and protein in the PVA sponges injected with the peptide increased significantly compared to control sponges, after 10 days. This effect was concentration dependent, with the optimum tested concentration being 10mg/ml. Experiments were also carried out on cell surface interactions. Binding of the peptide to fibroblasts was not inhibited by antibodies to the integrins a₁b₁, a₂b₁, a₃b₁, suggesting that collagen-receptor interaction in this case may be non-integrin mediated. From this work, it was shown that peptides isolated from collagens I and III were chemotactic for fibroblasts both in vitro and in vivo.