Logic Based Program Synthesis and Transformation : 11th International Workshop LOPSTR 2001 Paphos Cyprus November 28–30 2001 Selected Papers This book constitutes the thoroughly refereed post proceedings of the 11th International Workshop on Logic Based Program Synthesis and Transformation LOPSTR 2001 held in Paphos Cyprus in November 2001. The 13 revised full papers presented together with an invited paper were carefully selected and improved during two rounds of reviewing and revision. The papers are organized in topical sections on program transformation and equivalence program verification program analysis program development and program synthesis