Integrated Ocean Drilling Program (IODP) Expedition 303 was designed to sample and study climate records, including the composition and structure of surface or bottom waters and detrital layer stratigraphy indicative of ice sheet instability, at strategic sites that record North Atlantic Pliocene–Quaternary climate. The sites are distributed from the mouth of the Labrador Sea (Eirik Drift and Orphan Knoll) to the central Atlantic in the region of the Charlie Gibbs Fracture Zone. The sites were chosen on the basis of the importance of the climate or paleoceanographic record, adequate sedimentation rates in the 5–20 cm/k.y. range, and the attributes for a stratigraphic template based on relative geomagnetic paleointensity and oxygen isotope data.