An overview is given of the surface-to-bottom thermhaline, oxygen, nutrient, and baroclinic flow structures in the Aleutian Basin of the Bering Sea and the adjacent North Pacific, based on high-resolution field measurements in July 1993. A basic four-layer vertical structure is observed in the upper 1500 m. The 30-m top layer is warm, low in salinity and nutrients, and high in oxygen. Beneath it a 100- to 150-m thick temperature minimum layer is found, believed to be a remnant of winter convection. This is followed by a 300-m thick warm layer in which the main halocline, oxycline, and nutricline are located. Below it lies a layer of minimum oxygens and maximum nitrates and phosphates, centered at a depth of 900 m in the Bering Sea but rising to 400 m south of the Aleutians. This basic structure is disrupted in the vicinity of Amchitka Pass due to strong tidal mixing. The deep and abyssal waters of the Aleutian Basin differ substantially from those at comparable depth in the adjacent Pacific by being warmer (Δ=0.1 ¿C), less saline (Δ=0.01?), less dense (Δ=0.01 kg/m3), poorer in oxygen (Δ=50 μmol/kg), and richer in silicates (Δ=80 μmol/kg), nitrates (Δ=1.0 μmol/kg), and phosphates (Δ=0.3 μmol/kg). The highest silicate concentrations (>240 μmol/kg) occur at the foot of the Bering shelf. Unusual hydrographic conditions exist in an isolated tidal mixing basin in Amchitka Pass, where the bottom mixed layer is 600 m thick, 0.7 ¿C warmer, 0.14? less saline, and 21 μmol/kg less oxygenated than at comparable depths outside. Baroclinic currents indicate strong, deep, jetlike flows on both sides of the Aleutian ridge, weak shallow eddies in the middle of the Aleutian Basin, and somewhat enhanced flows near the Bering shelf edge. The Alaska Stream in July 1993 was 100 km wide, had a double core with a top speed of 0.54 m/s, and had a westward volume transport of 38 Sv, with 14 Sv below 1000 dbar. The north Aleutian current had a speed of 0.2 m/s and an eastward transport of 10 Sv, with 4 Sv below 1000 dbar. Off the Bering slope, both eastward and westward flows were observed, with volume transports near 7 Sv. ¿ American Geophysical Union 1995