Every migration involves two places: the one left behind and the one chosen. The demographer Everett Lee (1966) described migration as a weighing of factors at both ends, with obstacles in between.
Key idea
Push factors are reasons to leave the place of origin (war, few jobs, drought, persecution). Pull factors are reasons to go to a destination (jobs, safety, schools, family). Intervening obstacles stand in between (distance, cost, borders and visas, mountains, language). An intervening opportunity is a closer place that offers the same pull, so the migrant stops there.
Why it works
People rarely move for one reason. A farmer whose crops failed (push) may still stay unless a city offers work (pull) and the trip is affordable (no big obstacle). Factors are often grouped as economic (jobs, wages), social and cultural (family, religion, schools), political (war, freedom, laws) and environmental (drought, floods, climate).
| Push (origin) | Pull (destination) | |
|---|---|---|
| Economic | No jobs, low wages | Jobs, higher wages |
| Social and cultural | Discrimination | Family already there, schools |
| Political | War, persecution | Safety, freedom |
| Environmental | Drought, floods | Mild climate, fertile land |
Worked examples
Worked example: Sorting factors
A family leaves a drought-stricken farm and moves to a city where an uncle runs a business. Name the push, the pull and a possible obstacle.
- Push (about the place left): the drought.
- Pull (about the place chosen): the uncle and his business, so family and a job.
- Obstacle: the cost of the move or the distance.
Answer: Push: drought. Pull: family and work. Obstacle: cost or distance.
Worked example: The Dust Bowl
In the 1930s, drought and dust storms struck the southern Great Plains. Many families moved to California. Classify the factors.
- Drought and failed farms on the Plains: environmental and economic push factors.
- Hoped-for farm jobs and a mild climate in California: economic and environmental pull factors.
- The long, costly road west was an intervening obstacle.
Answer: Environmental and economic push; economic pull; distance as an obstacle.
Common mistake
Students sort a factor by whether it is good or bad. "Jobs in another country" is a pull; "no jobs at home" is a push. Ask: is this about the place being left, or the place being chosen? Good things at the destination pull; bad things at the origin push.