Twenty-first century Boston is home to a new wave of residents of every age and background moving to luxury apartments high above the city. While the needs of each owner are unique, there is generally a common design imperative – fewer enclosing walls to block views, consistent, harmonious finishes throughout, a more open, often larger and more “lux” kitchen, and a bedroom suite with sumptuous closets and a bath that feels like a day at a spa. The architect’s challenges are to achieve those goals in a space that can’t be expanded, with plumbing that often can’t be moved, and ceilings that are almost always a bit lower than anyone would prefer.