Trees in the city have become a major concern for the environment and sustainable development. Preserving our tree heritage is a way to make it last in order to meet this challenge. Faced with the growth of the urban area, the conditions of survival are often degraded, the developments will then have to take into account all the constraints to let the trees express their aesthetic, social, environmental and heritage potential. The urban tree is strongly dependent on its environment, conditioned by human activity which often appears hostile to its good development and health. As a structuring element of the landscape, it must be included at the heart of the project as a guiding component of the design. The success of conservation depends largely on the involvement of each of the actors. Solutions exist, regulatory measures are tools against the disappearance of trees from our landscape. Development solutions in response to the needs of space, soil, access to water and environmental richness are as numerous as the imagination of the designers allows.