This book constitutes the refereed proceedings of the Third International Conference on Typed Lambda Calculi and Applications, TLCA '97, held in Nancy, France, in April 1997. The 24 revised full papers presented in the book were carefully selected from a total of 54 submissions. The book reports the main research advances achieved in the area of typed lambda calculi since the predecessor conference, held in 1995, and competently reflects the state of the art in the area.