If you visited Portland, Oregon's Saturday Market prior to 2009, then you might remember a collection of vendor stalls arranged under the concrete approach ramp of the Burnside Bridge, spilling out to the south, wrapping around a ponderous and slightly run-down brick building, and continuing toward the historic Skidmore Fountain. And if you visit that site today, you'll notice things have changed.

The area under the Burnside Bridge is now a newly upgraded parking lot for the new University of Oregon facilities in the recently renovated (and LEED Gold-certified) White Stag Block, just north of the bridge. Saturday Market vendors now peddle their wares across the Naito Parkway in Governor Tom McCall Waterfront Park. Stalls stand under and around a new glass-and-steel pavilion built for that purpose.

And that ponderous brick structure — the 1892 Packer-Scott Building — is now part of the new headquarters for Mercy Corps, an international aid organization. THA Architecture designed the Mercy Corps Headquarters, which combines the renovated, 42,000-square-foot (3,900-square-meter) Packer-Scott Building with a four-story, 40,000-square-foot (3,700-square-meter) addition that fronts Naito Parkway.

The north and south walls of the addition adjoin the elder structure, deferring somewhat its sensibilities. Along those two facades, the newer building carefully maintains the minimum sense of solidity needed for continuity with its neighbor, while providing enough glazing to ensure that daylight permeates the interior even in Portland's sun-starved winters.

The building's entrance is marked by a break in the rhythm of the south facade, a four-story vertical channel that widens at the top and bottom floors. At the top of this channel, the building's fourth floor pulls back, visually punctuating the entry with glimpses of the sky beyond.

Meanwhile, less aesthetically constrained by proximity to the older building, the eastern end of the new building delivers abundant light and views. The upper three floors of this facade are virtually all glazing. The building's occupants enjoy views of Waterfront Park, the Willamette River, the city's historically industrial inner east side, and beyond, even Mount Hood.

Recently awarded LEED Platinum certification, the new Mercy Corps headquarters is highly environmentally responsible. According to THA, some 95 percent of construction waste was recycled. The building also includes a photovoltaic array, a green roof, and bioswales to address stormwater runoff.

Mercy Corps has a new home to be proud of, one which respectfully incorporates Portland's past in a global headquarters with forward-looking environmental responsibility.

Yours from Portland,