As with the prototype, model railroad tracks pass various types of scenery, including platforms and buildings, and cross over or join other tracks. To do this properly, without causing grief to the railroad company, a set of clearance standards are applied to the area around the track.

Sometimes when railroad companies merge, the clearance standards for the merging companies are different, and so a new set of clearance standards needs to be reached. This may mean cuttings need to be made wider, new tunnels may have to be cut, curves may have to be made broader, sidings may have to be moved, and signals and signs relocated.

For the model railroader the situation is similar, but with a little careful planning we can escape the clearance problems of railroad companies. We need to have a set of clearance standards to help us lay our track, and build scenery around that track. The clearance standards we set for ourselves should take into consideration the following: