Alan Charlton is to modern art what John Major was to modern politics. Working only in shades of grey, and with a back-to-basics approach to abstraction (at art school he chose to work on lengths of wood from a timber yard in place of conventional stretcher bars, and bought his paint from hardware shops), Charlton's work is more likable than it sounds.

He would like his paintings to be, he says, "abstract, direct, urban, basic, modern, pure, simple, silent, honest, absolute", and this austerely beautiful exhibition has moments of each of these moods and styles. I am surprised he does not mention poetic, though, because that's how the very different arrangements of work in each room come across. In the first room, there is a relationship between widths of paintings and their grey hue - the smallest being dark charcoal, the largest as silvery bright as the colour gets. If the room is flooded with sunlight, suddenly you see the various tonalities that grey can be, the dance of colour and rhythm contained in these austere-looking panels.

A second room functions as a bridge, with smaller framed works rather too flat in their greyness; this is the weakest part of the show. It is left to the final room to show us how monumental and evocative panels of one colour, repeated and stretched into different formats, can be.

In this last room, with its ornate floral cornicing and grids of sunlight thrown on to the floor through the window, Charlton's work lives up to his list. You think of vast things - maybe due only to September 11, skyscrapers are the most obvious association with the vertical panels - and you ponder light, space, beauty and small moments of grandeur. In this space, Charlton succeeds in his ambitious stated aims. Elsewhere it can all feel a little chilly, and you long for this artist to do one just streak of cerise. But then the weather changes and grey doesn't look so grey after all. Revisionism kicks in, within the space of one small exhibition.

· Until July 28. Details: 0131-552 7171.