Reducing crop dependency on synthetic chemical inputs is essential for moving towards a more sustainable form of agriculture that has less detrimental effects on the environment and human health. One solution is to optimise ecosystem services by increasing the functional diversity of plants within and around agrosystems. In this context of agroecological transition, the use of service plants is a promising and innovative approach. Service plants are a group of plant species cultivated to improve agroecosystem functions such as improving soil fertility, providing pest control and encouraging pollinators.This book provides a comprehensive overview of all types of service plants across different crops (field crops, vegetable crops, vines and fruit tree crops), in both temperate and tropical environments. It examines their mechanisms of action, the multiple services they provide (both benefits and drawbacks), the selection of service plants, and their implementation in different cropping systems and different climates. It encourages readers to take a step back from intensive farming systems and their specialisation, and to design complex, adaptive and resilient agroecological systems that address current challenges such as climate change, biodiversity loss, food security and energy resources.Suitable for researchers and students in agriculture, plant sciences, soil science, ecology and environmental science and agricultural advisers, this book provides a comprehensive review of service plants.