  A memoryless state sequence governing the behavior of a memoryless
state-dependent channel is to be described causally to an encoder wishing to
communicate over said channel. Given the maximal-allowed description rate, we
seek the description that maximizes the Shannon capacity. It is shown that the
maximum need not be achieved by a memoryless (symbol-by-symbol) description.
Such descriptions are, however, optimal when the receiver is cognizant of the
state sequence or when the description is allowed to depend on the message. For
other cases, a block-Markov scheme with backward decoding is proposed.
