Expanding Form is constructed on a grid pattern of twelve units – six reliefs and six recessive spaces. The cubes are combined with smaller interlocking geometric elements. Martin often spoke about the importance of the surface of her works, and described the spaces between the relief sections as areas of play, opposition and even conflict. She described her working process as free from ‘artistic interference’ and any ‘foreknowledge’ of the final appearance of the work. The aesthetic of ‘construction’ was often determined by following mathematical models such as the Golden Section and Fibonacci sequence.