The linear elastic behavior of frames with nonprismatic members is investigated by using isoparametric plane stress finite elements. It is determined that the conventional methods of analysis for these types of structures lead to erroneous results. Comparison of the fixed end moments, stiffness, and carry-over factors of nonprismatic members available in the literature with those computed by finite element analysis reveals large discrepancies. Based on an extensive study, sources and magnitudes of errors are presented. Recommendations for proper modeling by using conventional frame analysis computer programs are made.