This manual describes the procedure to prepare data for three analytical programs (LARZ, LARZ2, and LARZAK) as well as two plotting programs (PLARZ and PLARZK). Programs LARZ and PLARZ are for the analysis of reinforced concrete planar building structures subjected to base acceleration. Program LARZ2 is for static analysis of such structures subjected to lateral loads applied at floor levels. Programs PLARZ and PLARZK are for the analysis of a ″single-degree″ oscillator subjected to base acceleration.