New results obtained from a two-dimensional sequence analysis of the small heat shock protein (shsp) family are described. It is confirmed that the conserved C-terminal α-crystallin domain is essentially made of β-strands, most probably two groups of β-strands separated by a large loop. A direct correspondence between the putative β-strands that have been identified in shsps and the seven β-strands of a classical immunoglobulin-like fold is proposed. The hypothesis that the shsp family could belong to the immunoglobulin superfamily (IgSF) is consistent with the ubiquitous distribution and the multifunctional properties of the crystallins that are now emerging.