An approximate analysis was developed to investigate the postbuckling behavior of through-width delaminations in a laminated coupon. The analysis contains two parameters that are determined using a finite element analysis. After calculating the parameters for a few configurations, the approximate analysis was used to analyze many other configurations. Lateral deflections and Mode I strain-energy release rates obtained with the approximate analysis were compared with results from the finite element analysis. For the configurations analyzed, the approximate analysis agreed very well with the finite element results.