This talk will discuss (1) methods to verify the annual nature of sea scallop shell rings and (2) analysis of scallop shell ring data using linear mixed-effects models. Four sites located in areas closed to scallop fishing were repeatedly sampled for scallop shell heights and shells. Growth observed from the shell height measurements agreed from that inferred from the scallop shell rings under the assumption that the rings are formed annually. Stable isotope analysis of a limited number of shells also generally suggest that the rings are annual. Analysis of scallop growth from shell ring data presents special challenges because the first one or more rings are often missing or obscure, making absolute age determination difficult. For this reason, the distance between two successive rings on a shell is treated as an annual growth increment, with age unknown. The traditional method of estimating von Bertalanffy growth parameters from growth increment data (Fabens 1965) is known to be biased if the growth parameters vary among individuals, as is almost always the case. A mixed-effects version of Fabens' method will be presented that not only gives approximately unbiased estimates of mean growth, but also estimates of the individual variability of growth. Application of the method to scallop growth increment data indicates that scallop grow larger at shallower depths, in areas closed to fishing, and on Georges Bank compared to the Mid-Atlantic.