When it comes to building robot controllers, highlevel programming arises as a feasible alternative to planning. The task then is to verify a high-level program by finding a legal execution of it. However, interleaving offline verification with execution in the world seems to be the most practical approach for large programs and complex scenarios involving information gathering and exogenous events. In this paper, we present a mechanism for performing local lookahead for the Golog family of high-level robot programs. The main features of such mechanism are that it takes sensing seriously by constructing conditional plans that are ready to be executed in the world, and it mixes perfectly with an account of interleaved perception, planning, and action. Also, a simple implementation is developed. 1 Motivation In general terms, this paper is concerned with how to conveniently specify the behavior of an intelligent agent or robot living in an incompletely known dynamic world. One popula...