Mesh enclosures are probably the most popular housing choice for chameleons. They allow for excellent airflow and can also be used outside in the summertime to give a wide variety of species access to natural sunlight. However do bare in mind that in a fully mesh enclosure it can be more difficult to control the humidity and temperatures so although popular the world over dependent upon your individual requirements they may not suit all situations and a glass/mesh hybrid vivarium may be more suitable for some.