How important was Ostpolitik to the reunification of Germany?

A good way to approach this question would be to break down the concepts involved. Ostpolitik can be broken down into its political, economic and social consequences, and a strong answer should differentiate between these factors. For example, you could make the argument that politically, Ostpolitik represented an acceptance of the division of Germany, and economic support linked to these political decisions propped up the GDR's economy, perhaps prolonging its survival. BUT it also facilitated economic and social exchanges which broke down boundaries and contributed to the grassroots movements in 1989 calling for reunification.This question also calls for a consideration of long-term vs short-term causes, and top-down vs bottom-up change. Following the argument above, if you think that popular pressure in 1989 was a key element in persuading Helmut Kohl to pursue reunification, then you might place more emphasis on the importance of these economic and social exchanges. But if you think that the push for reunification came from above, then you might want to examine short-term factors such as the 'Gorbachev effect' and the impact of the 1989 revolutions on politicians' ideas, which challenged Ostpolitik's acceptance of division.Ultimately, it doesn't matter WHAT you argue as long as you make a convincing case for it. But it is important to make sure you demonstrate an awareness of the complexity of the question and the different ways it could be approached, rather than simply listing causes.