T-box genes encode putative transcription factors implicated in diverse developmental processes (Papaioannou, V.E. and Silver, L.M., 1998. BioEssays 20, 9-19). We have previously reported the embryonic expression patterns of T-box genes in mice (Chapman, D.L., Garvey, N., Hancock, S., Alexiou, M., Agulnik, S.I., Gibson-Brown, J.J., Cebra-Thomas, J., Bollag, R.J., Silver, L.M., Papaioannou, V.E., 1996. Dev. Dyn. 206, 379-390; Chapman, D.L., Agulnik, I., Hancock, S., Silver, L.M. and Papaioannou, V.E., 1996. Dev. Biol. 180, 534-542; Gibson-Brown, J.J., Agulnik, S.I., Chapman, D.L., Alexiou, M., Garvey, N., Silver, L.M., Papaioannou, V.E., 1996. Mech. Dev. 56, 93-101). Four of these genes (Tbx2-Tbx5) are represented in the mouse genome as two cognate, linked gene pairs (Agulnik, S.I., Garvey, N., Hancock, S., Ruvinsky, I., Chapman, D.L., Agulnik, I., Bollag, R., Papaioannou, V.E., Silver, L.M., 1996. Genetics 144, 249-254), and have all been implicated in playing important roles in limb development (Gibson-Brown, J.J., Agulnik, S.I., Chapman, D.L., Alexiou, M., Garvey, N., Silver, L.M., Papaioannou, V.E., 1996. Mech. Dev. 56, 93-101). To investigate the role of these genes in limb development, we cloned the chicken orthologs and report functional studies, as well as patterns of expression in the developing limbs, elsewhere (Gibson-Brown, J.J., Agulnik, S.I., Silver, L.M., Niswander, L., Papaioannou, V.E., Development, in press). This report details the patterns of expression of Tbx2-Tbx5 in chick embryonic tissues other than the limbs.