Working together on major projects: Basics of co-operation in federal impact assessments

Canada’s Impact Assessment Act (IAA) provides for the assessment of the impacts of major projects that are likely to have significant effects in areas of federal jurisdiction and for the mitigation of adverse federal effects. Some major projects that are subject to the IAA also require a provincial assessment. When this is the case, co-operation allows us to work together towards a single impact assessment process for such projects, with each jurisdiction maintaining authority over their respective areas of jurisdiction.

By working together, we can reduce duplication and enhance the efficiency and certainty of the assessment process. The goal is "one project, one review" and this approach is critical to the success of Canada’s regulatory approach for major projects.

On this page

• “One Project, One Review”
• Benefits of co-operation
• IAAC’s Approach to Achieving “One Project, One Review”
• Co-operation Mechanisms under the IAA
• Frequently Asked Questions

“One Project, One Review”

The federal and provincial governments have agreed to work toward implementing a “one project, one review” approach. The goal is to provide a single assessment experience for projects subject to both federal and provincial review, while respecting jurisdiction and upholding shared responsibilities to protect the environment and constitutional obligations to Indigenous Peoples.

Benefits of Co-operation

Guided by the principle of "one project, one review," co-operation offers many benefits while respecting the jurisdictional responsibilities of each government, including:

• Provide transparency, predictability and certainty to proponents, Indigenous partners, investors and stakeholders on how the federal and provincial governments will work together on "one project, one review" to reduce duplication in assessments while meeting the requirements of each jurisdiction;
• Demonstrate a shared commitment to enhancing efficiency and reducing duplication;
• Facilitate the alignment and integration of permitting processes and requirements into the environmental or impact assessment process and improve coordination and integration of federal and provincial permitting processes; and
• Enable the use of the full flexibilities in the IAA to defer to, to rely on and to work with and through, provincial processes under the co-operation mechanisms described below, to achieve "one project, one review".

IAAC’s Approach to Achieving “One Project, One Review”

IAAC launched a comment period in September 2025 on a Consultation Paper which outlined a proposed approach to working with provinces on the assessment of major projects through co-operation agreements. The paper described potential elements of these agreements and how they could realize the goal of “one project, one review” while respecting jurisdictional roles. The paper served as a foundational reference for discussions with provinces and provided an opportunity for stakeholders and Indigenous Peoples to share their perspectives on both the proposed approach and the types of provisions that could be included in co-operation agreements. We carefully reviewed and considered all feedback received to inform the development of agreements and their implementation.

Co-operation Agreements with Provinces

Co-operation agreements are tailored to each provincial context and while the specific provisions may vary between agreements, all agreements are guided by a shared objective: enabling “one project, one review.” These variations do not result in substantive differences in the overall approach.

Individual draft agreements with provinces are published for public comment as they are developed. Input received during these agreement-specific comment periods is carefully considered and used to refine each agreement prior to finalization and is also used to inform their implementation.

The agreements provide a framework for collaboration while fully respecting existing legal requirements and do not alter or diminish statutory obligations. All applicable provincial and federal legislative requirements continue to apply under co-operation agreements.

For a list of current agreements, consult Agreements related to assessments.

Visit Let’s Talk Impact Assessment to view and provide feedback on current draft agreements that are open for public consultation.

Co-operation Mechanisms under the IAA

To achieve “one project, one review,” the IAA provides a range of co-operation mechanisms that enable Canada to work with provinces and other jurisdictions to work together efficiently while minimizing duplication in impact assessment processes.

These include three primary co-operation mechanisms: early impact assessment decisions, substitution to a harmonized process, and substitution. Where these approaches are not used, the IAA still supports effective interjurisdictional collaboration through other tools that allow jurisdictions to align processes while carrying out their respective assessment responsibilities.

Below is a list of the different types of co-operation mechanisms.

• Early impact assessment decision (Section 16) under the IAA: a decision made at the end of the planning phase under Section 16 of the IAA that no impact assessment is required.
• Substitution to a harmonized process under the IAA: the Government of Canada and another jurisdiction jointly develop a single assessment process that replaces the federal process.
• Substitution to a provincial process under the IAA: a provincial jurisdiction’s assessment process replaces the federal process.
• Joint Review Panels under the IAA : the Government of Canada and another jurisdiction jointly appoint panel members for an independent panel to conduct the assessment.
• Delegation under the IAA: the Government of Canada delegates some tasks to one or more entities while remaining responsible for the overall assessment process.
• Coordinated Assessments under the IAA: the Government of Canada and another jurisdiction coordinate activities and, where possible, timelines and documents.

Frequently Asked Questions

Do co-operation agreements allow the federal government to defer entirely to provincial assessment processes?

Co-operation agreements can allow the federal government to rely on, or defer to, provincial assessment processes; however, the approach is determined on a project-by-project basis. These agreements provide a framework for federal and provincial governments to work together to avoid duplication while retaining their respective responsibilities and decision-making authorities, supporting “one project, one review” through a single, coordinated process from the perspective of proponents, the public, and Indigenous groups.

To make an early decision not to conduct a full federal impact assessment or to substitute to a provincial process, the federal government requires assurances that federal issues will be addressed through the provincial process and will be assessed on a project-by-project basis. This includes consideration of potential adverse impacts on the rights of Indigenous Peoples, as well as other federal interests. Where a co-operation agreement is in place, the federal government can remain engaged to support the integration of these federal considerations, including participation in related consultation activities.

How do co-operation agreements ensure Indigenous rights and consultation obligations are upheld under the IAA?

Respect for Indigenous rights and meaningful consultation remain central to federal impact assessments. Co-operation agreements with provinces are administrative, government-to-government arrangements that support collaboration and efficiency in impact assessments while ensuring that federal responsibilities continue to be met.

Canada maintains its commitment to the United Nations Declaration on the Rights of Indigenous Peoples and remains committed to upholding its duty to consult Indigenous Peoples in the context of individual impact assessments. Co-operation agreements do not amend, replace, or alter the rights, processes, or obligations set out in section 35 of the Constitution Act, 1982, and Canada remains committed to fulfilling its duty to consult with Indigenous Peoples in the course of specific project, regional or strategic assessments.

The Impact Assessment Agency of Canada also enters into agreements with Indigenous groups for the impact assessment of projects under the IAA. These agreements increase certainty by establishing clear, mutually agreed-upon processes and expectations early in the assessment process. The Agreement does not limit the ability of Indigenous groups and Canada to enter into such agreements with respect to assessments, nor does it limit the ability to incorporate Indigenous-led assessments in project specific impact assessments.

How do co-operation agreements differ between provinces?

Co-operation agreements differ between provinces to reflect differences in provincial legislative and regulatory frameworks, assessment processes, and administrative arrangements. Each agreement is developed collaboratively with the province and informed by extensive bilateral discussions, as well as feedback received during public comment periods, while maintaining the shared objective of enabling “one project, one review” in a manner that respects federal and provincial jurisdiction.

Although the structure of the agreements is broadly consistent, they include jurisdiction-specific details related to how Canada and a province work together during impact assessments. These details may address matters such as early engagement and information sharing, coordination of assessment activities, alignment of timelines, and co-operation on permitting and decision-making, consistent with the authorities of each jurisdiction.

Differences between co-operation agreements do not result in any commitments that differ from what is required or permitted under the IAA.