  Approximately 60 percent of all stars in the solar neighbourhood (up to 80
percent in our Milky Way) are members of binary or multiple star systems. This
fact led to the speculations that many more planets may exist in binary systems
than are currently known. To estimate the habitability of exoplanetary systems,
we have to define the so-called habitable zone (HZ). The HZ is defined as a
region around a star where a planet would receive enough radiation to maintain
liquid water on its surface and to be able to build a stable atmosphere. We
search for new dynamical configurations - where planets may stay in stable
orbits - to increase the probability to find a planet like the Earth. Therefore
we investigated five candidates and found that two systems (HD 41004 and HD
196885) which have small stable regions.
