A newly formed beach of limestone and concrete was watched for 2 years for progress of colonization, which was chiefly by Annelida, Crustacea, and Mollusca. An established mature beach nearby was studied for comparison. In the new beach it was evident that competition for foothold was not keen but rather that colonization was a very gradual process with only some half-dozen spp. capable of finding conditions suitable from the first and that other spp. must wait for improvement in the habitat. There was some evidence that the unfavorable conditions affected the survival of the young more strongly than the adults, for once established, growth rate was normal.