Lifecycle guide for System.Collections.Concurrent from Microsoft

All releases, patches, maintenance and support periods at a glance

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📅 Last update on 2026-04-10

What is System.Collections.Concurrent?

Automate product release and end-of-life management

Provides several thread-safe collection classes that should be used in place of the corresponding types in the System.Collections.NonGeneric and System.Collections packages whenever multiple threads are accessing the collection concurrently. Commonly Used Types: System.Collections.Concurrent.ConcurrentDictionary<TKey, TValue> System.Collections.Concurrent.ConcurrentQueue<T> System.Collections.Concurrent.ConcurrentBag<T> System.Collections.Concurrent.BlockingCollection<T> System.Collections.Concurrent.ConcurrentStack<T> When using NuGet 3.x this package requires at least version 3.4.

The entire lifecycle of System.Collections.Concurrent

The following figure shows you the visualised product life cycle of System.Collections.Concurrent. You can see all releases with the latest patch version, the long-term support characteristics (orange flag in the green circle, the periods for version provision, maintenance and support.