ABSTRACT: Most secretory proteins are synthesized, folded and assembled at the endoplasmic reticulum (ER) before forward transport in COPII coated vesicles. A stringent quality control machinery ensures that only fully folded secretory cargo are transported from the ER. During export, COPII coat subunits and specific cargo receptors bind to folded cargo for efficient packaging into ER-derived transport vesicles. Defects in cargo receptor activity influence ER quality control and yet it is not understood how these events are coordinated. The seminar will provide an overview of the ER quality control and COPII export processes. Unpublished findings on the role of the Erv26 cargo receptor in ER quality control will be presented that extend the work of Dancourt and Barlowe, 2009 [Traffic 10, p1006]. A review of this topic is provided in Dancourt and Barlowe, 2010 [Annu Rev Bioch 79, p777].