The sector model developed in 1939 by Homer Hoyt proposes that cities grow outwards from a central business district (CBD) in wedge-shaped sectors determined by factors like transportation routes, with different land uses developing in each sector. For example, in Chicago industry located along rail lines while housing developed north of the CBD. The multiple nuclei model from 1945 argues that cities form around several business centers rather than one CBD, taking into account increased car ownership. Both models have been criticized for not reflecting modern cities and their complexity.

1. Sector and Multiple Nuclei Models

2. Sector Model
- developed in 1939 by land
economist Homer Hoyt after a
study of 146 different cities,
mainly based on Chicago.
- According to this model, the city
develops in a series of sectors, not
rings. Certain areas are more
attractive for different activities.
- In the center is the Central
Business District. As the city
grows, activities expand in a
wedge, or sector.
- Hoyt argued that, in Chicago, the
best housing is developed north
from the CBD along Lake Michigan,
while industry was located along
the major rail lines and roads to
the northwest, south, and
southwest.

3. Chicago broken up into sectors

4. Influence of transportation on Chicago
Neighborhood Map Major Transit Lines

5. Criticisms of the Sector
Model
- Outdated: The model is too general
and doesn’t reflect cities today
- The model is based on the idea that
most people get to work by train.
- The model doesn’t take into account
urban renewal programs to develop
the inner-city.

6. Multiple Nuclei Model

7. Description
• Invented in 1945
• States that cities develop around a number of
different business centers or “nuclei”.
• These growth points create the different
sectors of a city.
• The model also takes into account people’s
ownership of cars and their ability to get
around more easily.

8. Example City: Los Angeles
- Broken up into a series of
neighborhoods
- No clear focus of the center ( No
real CBD).

9. Criticisms
• Neglects the height of buildings.
• Each zone is very complex. Does not provide a
general rule but more suggests a way to think
about cities.