TWENTY years ago, when David Gockley was appointed general director of the Houston Grand Opera (HGO), he took the reins of an esteemed regional company performing in a multipurpose auditorium. Today, HGO is internationally acclaimed, and performs in its own two-theater home, the $72 million Wortham Theater Center. The season has expanded from 27 performances in 1971-72, to 131 this year, and needless to say, the budget has grown as well, from $420,000 to $18 million.Mr. Gockley has gained a reputation not only for his acumen in gauging the response of his Houston audiences, but for his ability to orchestrate a season that mixes standard works, unfamiliar operas, with the best of United States musical theater. He has shrewdly blended international stars with the best American talent, and has encouraged young singers such as Frederica von Stade before they became international celebrities. Among the 12 world premieres HGO has presented during Gockley's tenure are John Adams's "Nixon in China" and Carlisle Floyd's "Willie Stark" (both seen in PBS telecasts), as well as works by Thomas Pasatieri, Philip Glass, Sir Michael Tippett, and Leonard Bernstein. Broadway saw HGO's highly acclaimed productions of Scott Joplin's ragtime opera "Treemonisha" (with a very young Kathleen Battle in the title role), and Gershwin's "Porgy and Bess" which also went on the road for a highly successful series of tours throughout the US and Europe. Last spring, Gockley mounted the company's most ambitious project to date - a five-production Mozart festival using both the 2,200-seat Brown Theater and the 1,100-seat Cullen Theater. It was a taste of European festival standards here on our shores, and it proclaimed once and for all that Houston must be considered an important part of any opera lover's yearly itinerary. This could never have happened before the Wortham Center, which opened in 1987, and it is the new facility that is Gockley's most visible achievement - built entirely with private funds, and begun just as the bottom was falling out of the oil market. For Gockley, the Wortham is, for the most part, a dream come true. "The greatest pleasure I think has been the whole upgrading of the ambiance. People really are proud that they are in what they perceive as a first-class facility. The acoustics are rich, the y are lush, they are very kind to the voice - singer friendly." Gockley's tenure as general director has been a progressive evolution for both his company and himself. He says that he always knew opera would be his career, though he had originally expected to be a singer. However, after a summer at the Santa Fe Opera, he decided instead to opt for a graduate degree at the Columbia Business School. From there, he went directly to Houston, in 1970, to be HGO's business manager. Two years later, he became the general director at age 27. "When I came here I had no idea w hat I wanted to accomplish, I just wanted a job," he states candidly. But during his early years, his penchant for well-rehearsed ensemble-style opera began to be noticed. In 1974, the world premiere of Thomas Pasatieri's "The Seagull" garnered national press attention, and Houston was on the operatic map. I asked Gockley what has thrilled him about the job: "I would say the way that ensemble has worked, whether in [that] early production of 'The Seagull' or in 'Porgy' or [Richard Strauss's] 'Der Rosenkavalier." Also, he says, "looking back, the repertoire of American works that we have done without bankrupting the company or losing the audience as everybody says you do when you do contemporary work, or American works, or both. "Some of the most satisfying experiences have been giving loving care to things like 'Porgy,Showboat,' 'Carousel,My Fair Lady,' and having them emerge with tremendous strength." Gockley says Houston is a bellwether for the country: Trends get rolling here several years before they "go" national. So when he describes the problems of sustaining an opera company in today's political and economic climate, he is sending a message to all opera companies around the country. "I think there's a big, big challenge in keeping opera and opera institutions alive and vital in a time of so many other civic priorities," he says. "Those civic priorities are going to shift even more as the slender white majority becomes a white minority, and all of the political and social and philanthropic [agendas] are going to shift away from the direction of Euro-oriented work. "Something that has appeal to 3 or 4 percent of the population I think isn't deserving of any media coverage, isn't deserving of any real corporate or foundation or government support.... I think that probably we need to follow on the heels of theater companies in being able to offer a lot more new work, find new composers, librettists, and stake them and develop audiences for them. It's not going to be the same old game." Gockley offered an outdoor production of Astor Piazzolla's "Maria de Buenos Aires" last June which gathered a large, ethnically mixed audience. A recently cancelled production will likely be replaced by Anthony Davis's "X," based on the life of Malcolm X. "We have an opportunity for creative programming. There is a genuine reason why this company should do and that is because it's an important work, it's important to our community, and we can add an artistic element that may not have been available in t he first production. I think ... we've got to make [new works] part of our core. "What I am trying to do here to shore up the organization is to try to offer diversity, but that diversity is still, and will remain, anchored in the great European works.... I think that a lot of our creative energies are going to have to be devoted to finding new works that are vastly appealing to a wider audience.... We're going to have to try to continually prove to the city that we are of economic and promotional value to it. And hopefully by doing this and by being this we can preserve our birthrig ht."