In 1992, the Ontario Ministries of Transportation and Municipal Affairs and Housing published the Transit-Supportive Land Use Planning Guidelines. The Guidelines were focused on transit-friendly land use planning and urban design practices. Since it was published, the Ontario government has introduced policies such as the Growth Plan for the Greater Golden Horseshoe (2006) and the updated Provincial Policy Statement (2005) to manage growth, encourage more livable and walkable communities and to develop sustainable, multi-modal transportation networks. At the same time, Ontario has made the growth of transit ridership a priority through more than $10.8 billion in transit investments since 2003. Recently, the Ministry of Transportation undertook to update the original Guidelines to support continued progress in building more compact, transit-supportive communities. The new Transit-Supportive Guidelines (draft) take a comprehensive approach, bringing together the most current thinking on transit-supportive urban planning and design and best practices in transit planning and delivery of customer-oriented transit service. The Guidelines emphasize the inter-dependent relationship between transit ridership and land use patterns: that higher density communities need dependable transit systems to thrive, and in turn, transit systems rely on transit-supportive land uses to sustain and increase ridership. This paper illustrates the close relationship between land use, transportation options and travel behaviour, and the strategic approaches needed to integrate principles and practices of land use, transportation and transit service planning to achieve sustainable communities and multi-modal transportation systems.