The present invention relates to processes and intermediates useful in the preparation of (R)-2-(7-(4-cyclopentyl-3-(trifluoromethyl)benzyloxy)-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl)acetic acid of Formula (Ia) and salts thereof, an S1P1 receptor modulator that is useful in the treatment of S1P1 receptor-associated disorders, for example, diseases and disorders mediated by lymphocytes, transplant rejection, autoimmune diseases and disorders, inflammatory diseases and disorders (e.g., acute and chronic inflammatory conditions), cancer, and conditions characterized by an underlying defect in vascular integrity or that are associated with angiogenesis such as may be pathologic (e.g., as may occur in inflammation, tumor development and atherosclerosis).