Since getting its funding - a mix of Heritage and Arts Council Lottery money, cash from the city, rents from ground-floor restaurants and the like - the project has forged ahead. You can already get a good feel for what it will be like as you wander through its clanging spaces, sidestepping builders who all - without exception - swig Irn-Bru from the bottle as if taking part in some corny TV advertisement. The structure of the new parts is up, restoration and conversion of the rest is at a reasonably advanced stage.

Although an early example of his sophisticated organic decorative technique, this was never a pretty-pretty Mackintosh building - he was really only dressing up a fairly standard commercial block on the orders of his employers, Honeyman and Keppie. Its industrial toughness transforms well into gallery space. The building will contain two main exhibition galleries - including a splendid tall-ceilinged one on the first floor - lots of smaller display areas, a 100-seater conference room, an education centre, and of course a cafe. It will house a permanent Charles Rennie Mackintosh centre, designed by Gareth Hoskins. From there, you can walk up to the opening bud of Mackintosh's rooftop turret. Or if you prefer you can survey the city from Page and Park's glassy new viewing gallery above the roof at the back.

Equally permanent will be the Lighthouse's "Design for Business" centre, effectively a suite of offices and meeting rooms where organisations with a design or architectural connection can place their representatives. But it is as an exhibition space that the Lighthouse will come into its own. As MacDonald says, "1999 is taken care of. We could have let out the space twice over. Now, we're looking to 2000 and beyond."

Lighthouse top floor gallery