Chapter 3: Migration Relocation Diffusion- spread through the bodily movement of people Migration- permanent movement from one place to another Geographers document where people migrate to across space. A form of relocation diffusion. Emigration- migration from a location Immigration- migration to a location Net Migration- difference between immigrants and emigrants If immigrants exceeds emigrants net migration is positive (net in-migration) If emigrants exceeds immigrants net migration is negative (net out-migration) Mobility- general term for covering all types of movement Circulation- short term repetitive cyclic daily movements Key Issue I: Why do people Migrate? Geography has no comprehensive theory of migration.