ActivitySim is everything you know and love about activity-based modeling. But better. Much better.

Meet ActivitySim—a state-of-the-practice activity-based modeling platform that is always improving. It is open source, purpose-built, and grounded in the principles of collaboration and modern software engineering.

The advantages to activity-based modeling have been known for quite some time. But the Association of Metropolitan Planning Organizations (AMPO) saw an even deeper industry need. They created a consortium of member agencies to drive this project. Their mission? To build and maintain advanced, open-source, activity-based travel behavior modeling software based on best software development practices—and to do it at no charge to the public.

And, just like that, ActivitySim was born.

Graphic showing the logos of all ActivitySim consortium members below the logo for the Association of Metropolitan Planning Organizations (AMPO). The logos below AMPO include Ohio Department of Transportation, San Francisco County Transportation Authority, Puget Sound Regional Council, Metropolitan Council, Atlanta Regional Commission, Southeast Michigan Council of Governments, San Diego Association of Governments, Chicago Metropolitan Agency for Planning, Metropolitan Washington Council of Governments, Oregon Department of Transportation, and Metropolitan Transportation Commission.

One of the best parts? It's always getting better.

Open-source technology is a huge movement. That's no secret. But an open-source activity-based modeling platform changes the very landscape of modeling. The deeper collaborative nature of ActivitySim being open source makes it state-of-the-practice and, perhaps even more impressively, means it is always improving. Each user has a say in its development and future direction.

You might be wondering how this works. It's simple. As additional members join the ActivitySim consortium, the user base grows, there are more resources for enhancements, and development progresses. As this occurs, ActivitySim becomes even more robust.

This technological advancement then comes full circle, helping all the consortium members with its improvements. Members benefit in several ways:

We aren’t just helping to build ActivitySim; we're also implementing it in multiple regions.

Our implementations include both replacements for trip-based models as well as existing activity-based models. Here are just a few examples.

SEMCOG (Southeast Michigan Council of Governments). Our team worked with the Southeast Michigan Council of Governments to develop a new activity-based model using ActivitySim that could more accurately capture and represent changing travel patterns and population levels. Read more in our case study »

CMAP (Chicago Metropolitan Agency for Planning). RSG deployed ActivitySim as a replacement for the Chicago Metropolitan Agency for Planning’s existing activity-based model to take advantage of the reduced runtime and increased usability of ActivitySim over their existing model.

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Want more?
Check out our ActivitySim
white paper.

ActivitySim has changed the very landscape of modeling. Learn more about how it started, where it's headed, and how it is helping agencies tackle some of their biggest challenges.

We're activity-based modeling experts and the lead developers and architects of ActivitySim.

We built it. We use it. And we would love to chat with you more about the ways ActivitySim may be able to help you get the answers you need.

Joel Freedman


David Hensle


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