在这篇文章中，我们将研究企业中的就业机会的创造和毁灭。我们将回答这个问题，是否大公司创造了就业，而小公司的贡献更少。还是年轻的公司创造了就业?谁破坏的就业机会最多?在危机中，丹麦的私营部门失去了18.6万个工作岗位。问题是在哪里以及如何重新创造这些工作岗位。这些问题是行业特有的还是普遍存在的?使用的数据是1980-2007年期间工作场所和公司的登记数据。数据的基本单位是工作场所。公司(商号)是法人实体。 A company can have many sites, and one of the ways companies can grow is by expanding with multiple sites. This can happen by mergers and acquisitions but can also happen by creating "daughter workplaces". It is therefore essential to look at workplaces and firms at the same time. A complication here is that firms switch ID over time because of change of ownership, mergers and divisions. Data must be corrected so that these administrative issues will not affect the survival of firms. The data are used in a way where we can cover firm birth and firm death, spin-offs and mergers. The analysis will make it possible to differentiate between net and gross creation of jobs because we can follow each single individual in and out of jobs. We have for Denmark found that size on its own does not have a big impact, but young firms are much more likely to contribute to a positive growth. For the U.S. it has been found that the growth in jobs comes from small businesses. A closer analysis though shows that the main factor here is the firm age. Thus, it is found that young firms net create the most jobs, but they are also responsible for the most job destructions.