As arts groups are gradually subtracted from the plans for the World Trade Center site, New York is losing even more ground on the global architecture scoreboard. Within days of the announcement that the Signature Theater Company — an off-Broadway group specializing in the work of American playwrights — would be no longer part of the Frank Gehry-designed arts complex, two European cities released plans for centers that will be significant steps forward in both architecture and the performing arts.

The two projects — the Elbe Philharmonic Hall in Hamburg, Germany and firstsite:newsite in Essex, England — share a cultural thread: The arts organizations that will occupy them drove the design and development. By contrast, the arts organizations at the World Trade Center site have had to sit by and wait — or drop out — as plans evolved around them. The difference in this approach to a city’s cultural life will be made manifest in short order: Both of these projects, which commenced in 2003, will open their doors before New York’s downtown performing arts center is scheduled to break ground — if indeed it ever does.

The Elbe Philharmonic Hall, designed by the Pritzker Prize-winning firm Herzog & de Meuron, will be the first permanent home of Hamburg’s North German Radio Symphony Orchestra, which recently gave a performance at Carnegie Hall. It will also be the cultural centerpiece of Hamburg’s HafenCity project, a 380-acre redevelopment zone situated between the historic Speicherstadt warehouse district and the River Elbe.

Like many cities, Hamburg is revitalizing its waterfront by reclaiming industrial port sites and transforming them into housing, cultural institutions, public parks, plazas, and new workplaces. When the project is completed, HafenCity will have increased the size of Hamburg’s city center by 40%.

The leading edge of this development will be the Elbe Philharmonic Hall. As the second largest city in Germany, Hamburg is asserting its commitment to becoming a new European cultural center. This building might seem like a small gesture, particularly when compared with the flurry of construction during the past 15 years in Berlin, but it is a statement of the city’s conviction that growth and new development will be led by public space and the arts.

In its design brief, Herzog & de Meuron writes, “The new space that will emerge here is designed to emphasize the public and the musicians to such an extent that, together, they actually represent the architecture.”

The trapezoidal site, at the tip of the harbor basin, is occupied by a modernist brick building designed by Werner Kallmorgen in the 1960s. The architects elected to retain this building, originally engineered to bear the weight of thousands of pounds of cargo, as the structural base for the concert hall. The base will also house parking, an interactive music museum for children, and back-of-house facilities. The new crystalline structure will create a covered public plaza that opens onto panoramic views of the city. This space will be a physical link between the old architecture of the city center and the new spaces of HafenCity.

This is not the first time the Herzog & de Meuron firm has transformed an existing industrial riverfront structure into a modern arts complex. Similar to the architects’ strategy for the Tate Modern in London, the plan begins by using the existing structure while carving out a soaring entryway. Both buildings incorporate a system of ramps and monumental escalators to carry visitors up into the space. But the galleries of the Tate are organized into the existing building shell, while the Elbe Philharmonic Hall floats above it.

The plan includes commerce as well as arts. The 2,150-seat hall is wrapped with a high-end residential development and five-star hotel. Still, the city and the firm should be commended for not only creating a new beacon of the arts, but for making some of the best views in the city available as public space.

An equally innovative arts complex is taking shape in England: firstsite:newsite, designed by New York-based architect Rafel Viñoly, is the name of the new home of firstsite, the eight-year-old arts organization in the historic town of Colchester. The aim of firstsite is to create a physical dialogue between artists and the community.

Education and participation are central to the philosophy here. Since its inception firstsite has developed new ways to experience art. Programs such as Artist Space created a venue dedicated to the interplay between artists and audience. In addition, firstsite works to address the practical needs of artists by offering professional services and support such as advocacy, business advice, mentoring, networking, and a retail space.

The charge for Mr. Viñoly was to reinvent the art gallery as a collaborative space where artists, community, works of art, and education can exist together seamlessly. To complicate matters, the town of Colchester is built on an ancient Roman city and the site selected for the project had been previously designated an English Heritage Archaeological site. This meant that in order for the building to be approved by the Historic Buildings and Monument Commission it had to preserve any potential Roman ruins beneath the site. So, in addition to creating a space to support this exceptional program, Mr. Viñoly designed an innovative weight-bearing structure that removed the need for deep foundations or intrusive piles to preserve the integrity of any ruins below.

The building, referred to as “the band of gold” for its golden colored cladding, an alloy of copper and aluminum, hugs the landscape as it follows the curve of an existing grove of trees. Rejecting the isolating walls of the traditional white box gallery, Mr. Viñoly integrates a large band of windows into the main gallery space, allowing visitors to experience the grove of trees from inside while making an important visual and cultural connection between the public space of the park and the public nature of the interior galleries.

Mr. Viñoly describes firstsite: newsite as “a new type of social building for cultural activity. It demonstrates how culture has moved from being an elitist preserve to a force for urban and economic development and community cohesion.”

Although the ultimate success of each of these buildings is still unknown, their momentum is unquestionable. Both of these carefully calibrated projects were driven by the needs of their local communities and the arts organizations they support. They were also both designed with sensitivity to their complex historic sites.

While there is no site with the unique politics and complexities of the former World Trade Center, the European projects serve as a reminder that a new development need not treat the arts as an afterthought.