Andy and Michael both commented on how GIL is complex and has lots of concepts. There is something rather easy that I can do to cut down on the concepts. GIL has abstract concepts for N-dimensional images/views/locators: PointNDConcept RandomAccessNDLocatorConcept MutableRandomAccessNDLocatorConcept RandomAccessNDImageViewConcept MutableRandomAccessNDImageViewConcept RandomAccessNDImageConcept Then it has refinements for them dealing with 2D: RandomAccess2DLocatorConcept MutableRandomAccess2DLocatorConcept RandomAccess2DImageViewConcept MutableRandomAccess2DImageViewConcept RandomAccess2DImageConcept Then it has further refinements dealing with pixel-based 2D images/views/locators: PixelLocatorConcept MutablePixelLocatorConcept ImageViewConcept MutableImageViewConcept ImageConcept Only the last ones have corresponding models. Although in theory one could represent things like video, 3D or lightfields as N-dimensional constructs, there are no existing models for them nor algorithms that take them. So one thought I have been toying with is removing the N-dimensional concepts until we end up needing them. Or maybe even removing the 2D concepts? That will cut down on the documentation with virtually no change in the code. Thoughts? Lubomir