Large white cabbage butterfly, Pieris brassicae (L.) is one of the most destructive pests in hilly regions of the India and several parts of the World and frequently causes heavy losses in marketable yield. Many control tactics have been followed to reduce the damage by this pest; although chemical control unfortunately till now a dominant option to fight against them. Besides harmful to the health, certain pesticides can cause severe damage to on-farm biodiversity as well. Therefore, biological control is now, emerging as an important component of pest management. The Meghalaya is a part of north eastern Himalayas (India) and one of the components of mega-biodiversity hot spot and exceptionally rich in terms of flora and fauna. In this book, attempts have been made to provide the information about different natural enemies of crop pests and their natural dynamics in cruciferous ecosystems, where we have tremendous scope to utilise them in biological control programmes against the target pests. Additionally, effects of different host plants on biology and behaviour of P.brassicae and its natural enemies have also been described.