Leaf proline accumulation, leaf chlorophyll stability, and germination at low osmotic potentials have previously been suggested as possible selection criteria for drought resistance in turnip rape (Brassica campestris) and rapeseed (B. napus) (Richards, 1978a). The feasibility of using these characters in a breeding program is reported. These characters were under significant genetic control and were responsive to selection. Broad sense heritabilities ranged from 40% for proline accumulation in both species to 55% for germination rate in B. campestris and 64% for chlorophyll stability in B. napus, however, narrow sense heritabilities for proline and germination were substantially lower. Their use as selection criteria for yield in a Mediteranean drought would be restricted since in B. campestris these characters were not related to yield while in B. napus only a weak association was observed between yield under drought and proline accumulation.