bottom-up
adjective [ before noun ]
MANAGEMENT uk/ˌbɒtəmˈʌp/ us/ˈbɑːṱ-/starting at the lowest levels or from the smallest details of an organization, system, plan, etc.:
In the bottom-up approach, investment analysts produce earnings forecasts on the basis of detailed research into the firm's activities.
The union prides itself on a being a member-driven, bottom-up organization.
He criticized the governor's proposal as a 'top-down solution to a bottom-up problem'.
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top-down