Ten years ago, it was the new ballpark on the North Shore, the drive to bring an upscale department store and other retailers to the Fifth and Forbes corridor, and a pitch for a multiscreen cinema and a "24-hour city."

What's the next "big idea" for Downtown Pittsburgh?

That's what the Pittsburgh Downtown Partnership wants to determine. It has approached Mayor Luke Ravenstahl and other key officials about developing a long-range plan for Downtown, the first since 1997, when PNC Park, Heinz Field and the expansion of the David L. Lawrence Convention Center were still in the planning stages, and the new Lazarus-Macy's department store hadn't even opened, let alone failed.

Back then, the North Shore casino wasn't even a thought, Downtown living was more oxymoron than anything else, and green was the color of an awning, not a whole new way of life.

"How we think about downtowns has changed completely since 1997," said Mike Edwards, the partnership's president and chief executive officer. "Groups like the Riverlife Task Force and the Green Building Alliance weren't even around back then."

With the Lazarus-Macy's store now being converted into condos, shops, restaurants and offices, the new Three PNC Plaza skyscraper going up on Fifth Avenue, and a major overhaul of Market Square in the works, Mr. Edwards believes it is time to map a Downtown strategy for the 21st century.

"There's a lot of people interested in doing stuff Downtown. We sense there could be a clearer direction. We did the stadiums. What is the next big idea for Downtown? As a community, it seems to me that we should have a say in that," he said.

Mr. Ravenstahl supports development of a new plan, spokeswoman Joanna Doven said.

If the experience of Calgary, Alberta, is any indication, a new long-range plan might be entirely different than one 10 years old. A decade ago, the Calgary plan concentrated on shopping, zoning and parking. The latest version emphasizes sustainability, energy efficiency, livability and neighborhoods, Mr. Edwards said.

He sees the same potential for Pittsburgh, given its reputation as a leader in green technology.

"Could Downtown Pittsburgh as a downtown be a LEED-certified place?" he asked. "Does that make us more competitive [for investment] both within the region, but, really, more nationally? That would be a tremendous thing if we could do it."

He also envisions greater emphasis on enhancements for pedestrians and bicyclists and streetscape improvements to enliven Downtown. He also would like to see zoning code changes making it easier for restaurants and cafes to add outdoor seating.

Those types of initiatives have the potential to "change almost the very nature of Downtown," he said.

Mr. Edwards also would like to look at ways to make Station Square, with its restaurants and entertainment, and the North Shore, with its office buildings, the stadiums and the new casino, more a part of Downtown.

With growing residential development in the Golden Triangle, there may be a need to look at more basic issues like construction start and end times Downtown.

"It's really a small thing, but talk to somebody who just spent $250,000 to move Downtown and all of the sudden the contractor can start at 5 a.m., that's a problem," Mr. Edwards said.

He said the city also must find ways to capitalize on the construction of the Three PNC complex, the Lazarus-Macy's and G.C. Murphy renovation projects and the plan by Point Park University to transform its campus into an academic village with shops, housing, recreation and theater to build a better Downtown.

Mr. Edwards estimated the cost of the plan at $1 million. It likely would be funded through a combination of public and private sources and developed over about 18 months through a series of public meetings and forums.

City planners and the Urban Redevelopment Authority would be involved, and the plan would need the approval of City Council. While the Downtown Partnership would help guide development of the plan, it ultimately would be a city document, Mr. Edwards said.

He believes the money would be well spent.

"If we want to get investment, both public and private, a Downtown plan is a cost of doing business," he said.

The last plan produced mixed results.

The stadiums were built after much controversy; a grocery store opened Downtown earlier this year, fulfilling another goal; the Roberto Clemente Bridge is closed to traffic and opened to pedestrians for special events, as the plan suggested; and more people are living in the Golden Triangle, as the plan envisioned.

But former Mayor Tom Murphy's ambitious plans to remake the Fifth and Forbes corridor into a retail mecca collapsed; there's still a dearth of specialty retailers; the multiscreen movie theater hasn't come about; and the 24-hour city has yet to awaken.