Cecil Balmond of Ove Arup & Partners, Daniel Libeskind's collaborator on the v&a Spiral, is now working on a project with Philip Johnson. Still prolific at 93, Johnson has designed a children's museum in Guadalajara, Mexico. Its four separate small pavilions and warped Platonic forms, occupy a man-made island in the middle of a lake. On Johnson's invitation, Balmond is designing a bridge to the mainland. Intended to give 'a sensation of movement' it will, he says, be based on 'old rope bridges in the Cameroons'.