Crime is lower when cities are greener: Evidence from South Africa supports the link: South Africa’s population is urbanizing at a rapid pace. The sheer rate of change poses challenges to planning for sustainable and liveable cities. Part of what make cities work is having green spaces, such as parks, sports fields, nature trails and street trees. These provide many social, ecological and economic benefits. Research from multiple countries such as Australia, China, Finland, India, the U.S. and South Africa has shown this. Aside from looking good and providing recreation, urban green spaces improve air quality, physical and mental health, and regulate storm water flows. They counteract urban heat islands, store carbon and create jobs. Some communities nevertheless oppose urban greening efforts because they fear that green spaces and street trees provide places for criminals to hide. Such fears are not unique to South Africa and have been reported from cities in both developed and developing countries. We conducted research to complement the evidence from the global north. Our study is the first ever national level analysis of the relationship between various measures of urban greenness and three different classes of crime: property, violent and sexual crimes. Our findings, based on research in South Africa, lend further credence to calls for urban greening to be adopted as a major strategy in cities—for both environmental sustainability, as well as social sustainability. We found that greener areas had lower rates of both violent and property crimes. But there was no relationship with the rate of sexual crimes. A more mixed picture was revealed when considering tree cover specifically, where property crime was higher with more tree cover, but violent crimes were fewer.