This figure represents a spiral whose centre is the intersection of two lines, one horizontal and one vertical, which divide the figure in four parts. In the top left part there is a text with ‘determine the objectives, the alternatives and the constraints’. In the top right part, ‘evaluate the objectives and identify and resolve the associated risks’. In the bottom right part, ‘develop and verify a (partial) solution or product’; and in the bottom left part, ‘review that solution and plan the activities for the next iteration’. The spiral goes from the inner side of the ‘determine the objectives, the alternatives and the constraints’, and moves clockwise and outwards through evaluate …, develop and verify …, review and back to determine… It comprises several revolutions.