[en] In the discussions about the safety of nuclear installations the question of building nuclear power stations below ground is being raised again and again. Almost all the experts in the field regard further investigations of underground construction as necessary or desirable. Although in present above-ground plant designs safety measures must ensure that the consequences of hypothetical accidents will in any case be accommodated without involving any hazard to the public, there are some question marks when it comes to ensuring protection against acts of war and sabotage. This contribution outlines the variants of underground designs of nuclear power stations and their feasibility at the present state of the art. The question is studied whether underground construction will increase the safety of the public as against present above-ground designs. Another problem considered is the question of whether the extensive protective measures required under the present licensing procedures and implemented in these plants already preclude any real hazard to the environment with a high degree of certainty, which would leave no necessity for underground constructions. (orig.)