Since 2018, the goal has been for CES to become carbon neutral in its operations by reducing greenhouse gas emissions and making offsets part of its conference budget. In 2018, CES approved a motion to green its operations, beginning with conferences. This led to the creation of the Sustainability Working Group. In 2019, CES reiterated its commitment in the Equity, Diversity, Inclusion and Environmental Sustainability (EDI&ES) Standing Committee term of reference (TOR-3). This document states that, in all its activities, CES must demonstrate proactive leadership in environmental sustainability, with an initial emphasis on conferences. This direction is further expressed as a CES National Strategic principle, in which CES aims to “take a leader role in sustainability, building opportunities to align work in diverse sectors in support of sustainability, and incorporating increasingly sustainable practices as an organization.” This direction has been embedded in the Conference manual since 2018:  take all reasonable measures to reduce the conference footprint.

The creation of the Sustainability Working Group was pivotal in the development of a Greening Rubric to expand on the sustainability expectation stated in the CES conference manual for annual conferences. This Rubric was first used for C2019. Since 2019, CES National and conference organizing committees have been working with the additional principles of mitigating the conference footprint and aspiring to make a positive contribution. This is how a carbon offset contribution (which is one among various actions in the Greening Rubric) was added on a volunteer basis in 2019 and on a mandatory basis in 2020 and 2021, and has now become a routine in the conference budget.

Decisions on where to invest the offset should be advised by EDI&ES volunteers and/or Active Reconciliation volunteers, with the support of the National EDI&ES Standing Committee, which is responsible for overseeing our Truth and Reconciliation Commission of Canada (TRC) commitments as well. For instance, after C2021, the Sustainability Working Group worked with Active Reconciliation volunteers and EDI-ES committee members to advise on how to use the carbon offsets. Money collected via carbon offsets were invested in local First Nation home efficiency projects from an award-winning group called Indigenous Clean Energy.

For C2023, the following criteria will be used to select a project which will be financed with the money collected.

1. Project seeks to improve equitable living conditions
   (such as a local project that is good for social and ecological health; project with a positive influence on active reconciliation and UNDRIP principles, etc.).

2. Project that does no more harm
   (e.g., project that is not subject to “leakage,” i.e., emission reductions obtained in one area don’t result in greater emissions somewhere else).

3. Additionality of emission reduction
   (i.e., the offset investment enables greenhouse gas reductions that wouldn't otherwise have happened).

4. General quality of the offset project
   (e.g., a project that meets the highest certification standard; offsets come from a reputable source, are verified, and certified by a third-party reputable assurance provider; emissions reductions occur immediately i.e., within the year the offsets are bought or earlier; project is registered with a carbon offset registry, to ensure offsets are only sold once and not double-counted; project is monitored to make sure what was promised is executed, etc.)

5. Project generates permanent positive impact
   (i.e., the emissions reductions are lasting and cannot be reversed; project specifically helps the world transition off fossil fuels.)