Abstract: Corner modules have recessed, handrail-receiving mounting pockets bounded top and laterally by non-recessed boundary edge portions, but open at their bottom ends, and vertically taller than the end face of the handrail interval of steepest incline. The mounting pockets of the corner modules are factory-produced with very neatly made edges, whereas the end faces of handrail intervals are cut on-site for a particular installation, and tend to have cutting imperfections at the end face edges, such as chips, splinters, burring, edge waviness, etc. The handrail intervals, having underfaces with longitudinal slots, are mounted on baluster tops provided with articulate flanged connectors having tabs fitting firmly but slidably into the underface slots; thus the handrail intervals can be adjusted until they assume their needed relative positions, whereupon screws passing through holes in the flanged connectors penetrate the handrail underface deep within an underface slot.