Martin and the contributing writers present the thesis that mobility of semi-peripheral states to the core world-economy is a very rare phenomenon. Indeed, they even go so far as to suggest that it is the very set of social and institutional ruptures that were necessary to achieve semi-peripheral status which often create the social and political forces that prevent any further advances. Economic pressure from core nations and intense competition within the semi-periphery are cited as being foremost among these factors. Such general topics occupy the first few chapters of the book, while the later chapters examine specific semi-peripheral countries in depth. The final interpretation provides a better understanding of this segment of the world-economy and of the transformational possibilities of the capitalist world itself. Students of both world-economy and the social and political conditions of the semi-periphery should find this an interesting study.