The laws regulating local government powers and services, as well as their financing, tend to be uniform within each country, paying no particular attention to the size of municipalities or the urban or rural nature of local governments. However, beneath this legal uniformity lies a very diverse practical reality. Only large urban municipalities can provide certain services (such as public transit) that require extensive infrastructure, high technical capacity and substantial funding. In addition, rural municipalities face great difficulties in the indirect management of services (through contracts with companies) due to their limited capacity to define contractual relationships and monitor compliance. This technical difficulty is particularly evident in public private partnerships (PPPs), which are unaffordable for rural municipalities. Similarly, although local financing laws usually offer a uniform system for all municipalities, in practice the financial sources of urban and rural municipalities are very diverse. Urban municipalities can obtain significant revenue from their own taxes and fees, with regional or state financial transfers playing a complementary role. In contrast, rural municipalities are more dependent on transfers. This explains why, in some countries, supra-local financial transfers include levelling or equalization instruments for the benefit of rural municipalities.