渐进主义（英语：Incrementalism），又称渐进调适或渐进模型，是一个有关决策制定的理论模型，由美国政治科学学者查尔斯·林布隆（Charles E. Lindblom）在批判传统理性模型的基础上提出。渐进调适理论认为，决策制定的实际过程，例如分析问题、明确目标、提出方案、优化选择等，并不完全是一个理性过程，而是对以往的决策行为不断补充和修正的过程。因此，决策制定实际上是根据以往的经验，在现有的政策基础上实现渐进变迁。

In politics, the term Incrementalism is also used as a synonym for Gradualism.

Incrementalism is a method of working by adding to a project using many small incremental changes instead of a few (extensively planned) large jumps. Logical incrementalism implies that the steps in the process are sensible. Logical Incrementalism focuses on "the Power-Behavioral Approach to planning rather than to the Formal Systems Planning Approach." In public policy, incrementalism refers to the method of change by which many small policy changes are enacted over time in order to create a larger broad based policy change. This was the theoretical policy of rationality developed by Lindblom to be seen as a middle way between the rational actor model and bounded rationality, as both long term goal driven policy rationality and satisficing were not seen as adequate.