4-(2,2-Difluoro-benzo[1,3]dioxol-5-ylmethyl)-piperazine-1 -carboxylic acid (4-chloro-pyridin-3-yl)-amide is described, which is useful as a FAAH modulator. 4-(2,2-Difluoro-benzo[1,3]dioxol-5-ylmethyl)-piperazine-1 -carboxylic acid (4-chloro-pyridin-3-yl)- amide may be used in pharmaceutical compositions and methods for the treatment of disease states, disorders, and conditions mediated by fatty acid amide hydrolase (FAAH) activity, such as anxiety, pain, inflammation, sleep disorders, eating disorders, energy metabolism disorders, and movement disorders (e.g., multiple sclerosis). A method of synthesizing 4- (2,2-difluoro-benzo[1,3]dioxol- 5-ylmethyl)-piperazine-1 -carboxylic acid (4- chloro-pyridin-3-yl)-amide is also disclosed.