This chapter discusses 5G network planning and optimization by giving an overview to the planning methods and processes applicable from the 4G era, and new considerations for 5G. It also discusses the key requirements for 5G planning, including flexibility and high reliability, need for multiple network and radio access technology layers, high mobility and connectivity between networks and devices, precise positioning, and high security. The chapter provides generic guidelines for the 5G core network dimensioning, including capacity estimation and reservation, dynamic capacity allocation, and cloud-aided methods. It further details aspects on 5G radio network planning, including coverage, capacity, and parameter planning, evolved radio link budget and its adjustment based on use cases. The balancing of these parameters depends on the wanted costs; in the optimal network, the return of investment is a balance, not too expensive as it wastes the capacity, not too low cost as the customers' churn increases along with the reduced quality.