Thin filament integrity is important for the ordered structure and function of skeletal muscles. Mutations within genes that encode thin filament and thin filament-associated proteins can cause muscle disruption, fiber atrophy and alter fiber type composition, leading to muscle weakness. Analyses of patient biopsy samples and tissue culture systems provide rapid methods for studying disease-causing mutations. However, there are limitations to these techniques. Although time consuming, many laboratories are generating and utilizing animal models, in particular the mouse, to study the disease process of various myopathies. This chapter reviews the use of mouse models for thin filament diseases of skeletal muscle and in particular, concentrates on what has been achieved through the generation and characterization of transgenic and knock-in mouse models for the congenital thin filament disease nemaline myopathy. We will review potential therapies that have been trialled on the nemaline models, providing indications for future directions for the treatment of nemaline myopathy patients and muscle weakness in general.