Abstract: Disclosed are hollow fibers suitable for use in dialysis in an outside-in configuration. For such fibers, it is desirable that the fiber have a low albumin sieving coefficient and have a permeability high enough to be considered a High Flux dialyzer, and it is desirable that the outer (blood-facing) surface have a sufficiently small roughness and be hydrophilic. It is desirable that there be a selective layer on the outer surface and, interiorly of that, a porous structurally supportive region, which may contain elongated macrovoids. Such a fiber may be spun through a triple-concentric spinneret that produces a bore liquid surrounded by dope surrounded by a shower. The shower and the coagulation bath may be pure water, which is a non-solvent. The process may be performed at room temperature. Spinning parameters are discussed.