Abstract: Novel CFTR corrector compounds that are effective in rescuing halide efflux in a cell are provided. Also provided are methods for treating protein folding disorders (e.g., cystic fibrosis). The methods include administering a CFTR corrector compound or pharmaceutically acceptable salt or prodrug thereof. Methods of screening for CFTR corrector compounds are also described herein. The methods of screening include contacting a cell that endogenously expresses a CFTR mutation with the compound to be screened and detecting a rescue of halide efflux from the cell.