This document discusses regulating network industries using evidence from Rwanda's mobile phone network. It finds that: 1) Taxing mobile networks has spillover effects, and ignoring network effects can underestimate the true welfare cost of taxes by over $1 per $1 raised. 2) Universal service obligations that require remote area coverage provide benefits not just to those areas but to cities as well, with over 75% of the benefits accruing to individuals unaffected by the expanded coverage. 3) Introducing competition into a mobile network can have complex effects, lowering prices but also potentially reducing network effects and business stealing, with models finding that competition may increase welfare by over 1% of GDP.