These programs calculate principal stresses, strains and directions from any rosette readings. The appropriate values are read in, the angles placed in the range 0 to 180° and the strains arranged in descending order. Next the necessary quantities are calculated and checked; a choice of output formats is provided together with an error message and diagnostic information if the check fails. One of the programs is written to accept strain readings on punched cards, the other accepts voltage readings on paper tape from a data logger. The programming language is FORTRAN IV. The programs have been used on an ICL 1903A computer