The article concentrates on the work of the master stair builder, Harry Waldemar of Ardsley, N.Y. Waldemar's scale models of stair construction, as a way of recording his knowledge, are described. The traditional construction of stairs is outlined step by step in great detail. Areas covered are the use of the pitch board, the construction of the closed stringers, the open stringers, the treads, the balusters, the risers, the newel, and the handrailing. -- AATA