Urban trees are indispensable in making our cities livable. In the past 15 years, researchers in urban forestry have developed methods of quantifying the ecosystem benefits provided by urban trees. In our increasingly paved cities, tree services are essential, as it has become clear that poor practices in tree selection and soil preparation have reduced the potential benefits of planting such trees. As our metropolitan areas are so heterogeneous, not all trees will do well in all sites. However, the most ubiquitous constraint to healthy, urban tree growth is soil compaction and limited accessible soil volume, leading to stunted trees that cannot withstand increasingly hot and dry summers. Fortunately, there are many practices that can overcome these challenges.