The problems of repertory grid analysis fall into two main groups: (i) general scaling problems; (ii) specific methods of the simplification of the grid data. Some problems of psychological scaling are considered including 'ranking' versus 'rating', equal interval assumption, and comparison of constructs. The grid analysis methods of principal component analysis, multidimensional scaling and cluster analysis are described briefly, whilst a hand-sorting cluster-type method is demonstrated. Methods for processing pairs and groups of grids are also considered.