The cystic fibrosis transmembrane conductance regulator (CFTR) is an ion channel that once phosphorylated by PKA is gated by ATP binding and hydrolysis. When open, this channel allows chloride ion flux. The CFTR gene was cloned and has been of interest as a therapeutic target since the first observation that a nucleotide substitution found in patients with cystic fibrosis encodes for a trafficking-deficient mutant channel termed DeltaF508. To date, at least 136 allelic variants of CFTR have been associated with patients that have cystic fibrosis. The CFTR ion channel is expressed in the respiratory tract, sweat glands, intestinal tissue, and pancreas, and decreased surface expression or function of mutant channels in these tissues is consistent with disease symptoms. To date, specific activators and trafficking modulators that normalize surface expression and function toward wild-type levels have shown promise as therapies for cystic fibrosis.