This book constitutes the strictly refereed post-workshop proceedings of the Sixth International Workshop on Logic Program Synthesis and Transformation, LOPSTR'96, held on board a ship sailing from Stockholm to Helsinki, in August 1996. The 17 revised full papers were carefully selected from a total of initially 27 submissions. The topics covered range over the areas of synthesis of programs from specifications, verification, transformation, specialization, and analysis of programs, and the use of program schemata in program development.