Concrete has an advantage over most other materials—it's sustainable as well as green. It won't burn, be destroyed in wind events, or rot. It's not a source for mold and can't be damaged by termites. When used to build structures, concrete is thermally efficient, and by properly designing mixes, structures and slabs can have service lives of 100 years and more. This is the message Shepherd, director of sustainable development for PCA, is charged with promoting to designers and owners.

Shepherd is well trained for his job. He graduated from college with an architecture degree but spent most of his life working on the construction side rather than designing. His employment with companies over the years includes technical sales, real estate investment and development, concrete home promotion (for the PCA), and finally sustainable development. He says the PCA created his position because the public is very aware of the concept of green through various organizations, such as the USGBC and its LEED program, but not about sustainability. The green focus emphasizes the components, while sustainability takes a holistic perspective: the project and its local context, how it performs, and the life of the structure.

Part of Shepherd's job involves collaboration with other concrete organizations for educational and promotional efforts. In the past year, 22 allied associations joined the concrete industry's Joint Sustainability Initiative, working to promote the sustainable value that concrete offers to society.

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