Some people come to office with a reputation, some with an ambition and some with an idea. Henry Cisneros moved into the mayor's office in San Antonio in 1981 with all three.

His reputation was as a capable, innovative urban expert. His ambition was to rise higher than any other Mexican-American politician ever had. His idea was to harness economic development as the primary tool for ending poverty in his city.

Nearing the fifth anniversary of his election, Cisneros and San Antonio are at a critical juncture. His popularity is high. His city's growth has been steady. But it is still not clear whether he has found a formula for making that growth pay off for the mostly poor, mostly Mexican-American people who first put him in office.

The city he runs is a study in contrasts. Its northern and western edges are exploding with new office buildings and shopping centers. New projects, ranging from a biotech research park to a $125 million Sea World, guarantee that growth will continue.

But the downtown retail section, despite some new hotels, is bedraggled, with some old-time quality merchants abandoning the fight against traffic tie-ups and the burgeoning suburban malls. And in the large barrios on the west and south sides, chronic underemployment is widening the income gap between "the two San Antonios."

While Cisneros seems secure as long as he wants to be mayor, an incipient taxpayers' revolt has emerged in recent months to threaten the long-term strategy by which he hopes to vault his city -- and himself -- into national leadership.

All this leaves the handsome, 38-year-old mayor in something of a quandary. He talks proudly of "the sense of lift" his own energetic leadership has imparted to the community. Wherever a visitor goes, developers and barrio organizers affirm that Cisneros has been instrumental in developing "consensus" on San Antonio's goals. But Cisneros concedes that "the hardest thing to do in a free-enterprise system is to direct growth" -- as he must do to reach his social and economic objectives.

"My belief has been that we had to change the income mix in our city," Cisneros said. "Jobs and economic development are the central driving force . . . . We have made progress, but it's not as strong as I would have liked to have it."

The nervousness is well-founded. One recent morning, Kenneth Daly, the city's director of economic development, pulled out a sheaf of Commerce Department figures showing that, between 1983 and 2000, San Antonio's per capita income, in constant dollars, is projected to fall $340 further behind the national average -- bumping the nation's tenth-largest city to 237th in median income.

San Antonio's problem is simple to define but difficult to solve: The prosperity and profits on its northern fringes are not trickling down to its central core and its mostly minority south, east and west sides.

An analysis of statistics made available by the Economic Development Foundation, the business-recruiting arm of the San Antonio Chamber of Commerce, shows a widening gap between the city's have and have-not populations. From 1982 to 1984, the first three full years of Cisneros' administration, per capita income in the city's three lowest-income areas, all dominated by Mexican Americans, declined 9 percent. In the same span, the three highest-income areas, all north-side areas with more than 90 percent Anglo populations, saw their per capita income rise more than 7 percent. In those years of recession and recovery, outside economic forces apparently overwhelmed Cisneros' strategy.

The pattern of San Antonio's growth was set long before 1975, when Cisneros, with his bachelor's, master's and doctorate degrees from Texas A&M, Harvard and George Washington universities, was first elected to the city council of his home town.

The north side of town, where the land rises in tiers towards the Hill Country homeland of Lyndon B. Johnson, provided the home sites more attractive to the wealthier Anglo families who controlled San Antonio's civic life. They located the international airport, the health sciences center, the San Antonio branch of the University of Texas on their side of town. With the emergence of Austin, 78 miles to the northeast, as a major growth center, the pull in that direction has become stronger.

San Antonio's south side, flatter and less prepossessing, was shared by the Mexican Americans and the families of the service members and civilian employes of the many military bases. Promoting the area has been a tough struggle. Daly said the tax incentives the city has offered firms to locate on the south side have not been sufficient. "The companies listen, but then they tell us they want to bring their customers to a prestige location," he said.

Downtown San Antonio shows signs of both growth and decay. This winter, the famous Riverwalk has been undergoing repairs to some of its rotting walls and bridges. Sears and Montgomery Ward have closed their downtown stores in the past two years. Pincuses, a 52-year-old local quality merchant, recently gave up the struggle. But the convention center is being expanded and a 1,000-room hotel is scheduled to start construction this month. "We're kind of behind the 8-ball right now," said Frank Perry, the director of downtown development, "but we feel there will be a reward for those businesses that hang in there."

One center-city bright spot is the Vista Verde project Cisneros promoted while a council member. Federal UDAG (Urban Development Action Grant) funds cleared an old slum area and put up a plant that Control Data Corp. (CDC) ran for five years. When CDC retrenched last year, Gene Rodriguez, a former San Antonio economic development director, organized a company called Mil-tronics to sublease the facility.

The bright, clean plant now employs about 225 people, almost all from the immediate area, at an average (nonunion) wage of $5.35 an hour. "After three months," Rodriguez said, "we've got our first military contract, we've increased productivity and we've added about 25 people to the work force."

Rodriguez said he thinks more firms may be attracted to the center city if they are convinced they can find trained workers. But San Antonio did not get a branch of the University of Texas until 1973, and its engineering program graduated its first students only in 1984.

Down the street is a new "business incubator" building, a joint property of CDC and a local developer, where fledgling firms can rent space and share conference rooms, duplicating and computer facilities while they are in their developmental stage. The building is only about 20 percent occupied, but Robert M. McKinley, who succeeded Rodriguez as its manager, said 16 of the 26 businesses are minority-owned. Most are service firms. "The key challenge is to get manufacturing tenants to come to the center city to provide a market for the services," McKinley said.

A third component of the Vista Verde project, an indoor shopping mall, has had a checkered history. The original developer ran out of money and the mall now stands half-empty, waiting for a promised push from the new owners.

While downtown struggles, the growth has continued in the northern sector -- but not particularly on the path Cisneros charted. His initial thrust was to make San Antonio a new Silicon Valley high-tech center. But when retired admiral Bobby R. Inman picked Austin over San Antonio in 1983 as the site for the prized Microelectronics and Computer Technology Corp. (MCC), a research consortium, he told Cisneros that his city's "superb presentation" had been undercut by the absence of a quality education system, at all levels, and a skilled labor pool.

He advised Cisneros to redirect his efforts toward biotechnology, using the existing complex of military and civilian medical research and treatment centers in the city, including the South Texas Medical Center.

Biotechnology has become the conscious focus of a major cooperative effort by city officials, business and academic leaders. A health-careers magnet high school opened in 1984 and has 386 students. Although the school is roughly 18 miles northwest of downtown, its enrollment mirrors the diversity of the city.

Within the next 90 days, the Texas Research and Technology Foundation expects to acquire a 1,500-acre site, west of the city, to house the University of Texas' biotechnology institute and a projected set of allied private research and manufacturing firms. Cisneros talks of 100,000 medical and biotech jobs in the San Antonio area by the year 2000, but the location, about 16 miles from downtown, raises questions of access.

In a 1982 interview with the National Journal, Cisneros said, "I am convinced that you are not going to be able to get minorities jobs in the suburbs. If you put yourself in the position of a minority person living in the culture of poverty, you can't be expected to drive a rickety old car 12 miles to the suburbs and be there on time and not have an absentee rate."

So far, the biggest new "industry" to move to the area since Cisneros became mayor is the Sea World theme park 14 miles northwest of downtown, announced last year, which is projected to provide 1,500 jobs when it opens in 1987. Many of the jobs will be seasonal and low-skilled. But to land Sea World, San Antonio had to agree to a seven-year moratorium on annexation and the state had to guarantee tax abatements of $6 million for the first 15 years.

Some of Cisneros' critics contend that the continued reliance on tourism shackles the city to a low-wage future. Helen Ayala, the president of COPS (Communities Organized for Public Service), the major organization of the Mexican-American community, said "tourism has been part of our history . . . . We are looking for better for our children."

But Sea World's developers agreed to help build a freeway from the site into the west side, and Ayala said she believes it will attract business to her area.

Ernie Cortez, a COPS veteran who now organizes throughout the Rio Grande Valley, is doubtful. "We don't mind being part of the consensus," he said, "if it means real economic opportunity for everybody. But the danger is that the consensus is beginning to be 'a job is a job' -- whether it's Sea World or McDonalds . . . . I'm real skeptical how well we've been targeting for jobs that mean real economic opportunity."

Such comments are rare in San Antonio. Cisneros has built a spirit of cooperation among the city's diverse elements, using not just his persuasive powers but his national prestige as the current president of the National League of Cities and the publicity he received as a potential 1984 Democratic vice presidential candidate.

At his urging, COPS and the Chamber of Commerce lobbied side by side in Austin for passage of an education bill that has brought $70 million in new state aid to San Antonio area school districts. More than 145 organizations and about 500 private citizens joined forces on a Target '90 Commission, which submitted a challenging report on the city's future.

Cisneros carried every precinct in the city in winning 73 percent of the vote in his 1985 reelection victory. He has persuaded a remarkably broad swath of the city's leadership to endorse his economic development plans. Edward B. Kelley, former chairman of the board of the North San Antonio Chamber of Commerce, calls Cisneros "the single best asset we have. He's charismatic. He's a planner. He's got a vision for the city. And he's brought together what could be polarized communities."

But the consensus was jarred -- and Cisneros' standing at least temporarily challenged -- last November in the unexpected defeat of a referendum on fluoridation of city water. Despite endorsement by the mayor, other civic leaders, the Roman Catholic hierarchy and the local press, the referendum was defeated by 3,266 votes of 81,160 cast.

It was an embarrassing setback for a city trying to market itself as being on the cutting edge of scientific and technological change. "We're hung up on an issue of the Fifties," said Kelley.

The general of the anti-flouridation forces was an unlikely figure, 63-year-old C.A. Stubbs, a retired Air Force civilian technician and leader of the Homeowners-Taxpayers Association, a 3,000-member group dominated by retirees. Like other populist tax-revolt groups, Stubbs' organization uses call-in radio shows and other inexpensive methods to spread the charge that the politicians and the special interests are conniving.

"Henry Cisneros is a smart young man," Stubbs said in an interview, "but he listens to the wrong people. The developers' . . . priorities are wacko. They're trying to force-feed growth faster than we can afford it."

Stubbs is circulating petitions for an August referendum to limit the increase in city spending. He has been touring the city with charts asserting that in the last five years, city spending has risen more than 200 percent, while population has grown less than 10 percent and inflation less than 50 percent.

Cisneros and his business allies contend that the blame is misplaced. They cite figures showing that San Antonio's municipal taxes are barely half those of Austin and one-third those of Houston and Dallas. Property taxes have risen, they say, mainly because of a state-ordered mandatory reassessment program. Much of the spending increase, they contend, represents long-delayed investment in transportation and sewage treatment and improvement in the city's long-neglected schools.

But Cisneros is trimming his sails. In his 1986 budget, he proposed freezing property tax rates, increasing the homestead exemption for senior citizens and taking "a tough and self-critical" look at city spending. Scheduled merit pay increases for city employes were frozen in January and a charter commission that was to consider raising salaries for the mayor and council members was killed.

In an interview, Cisneros said he recognized the "natural collision" between the interest of retirees "who find San Antonio desirable as a low-wage, low-cost community" and the "younger population that recognizes its economic stake in growth." He said he was confident that the "future-oriented" forces will prevail.

The challenge at home comes at a time when Cisneros' national reputation as an innovative mayor and dynamic political figure continues to soar. It leaves him in a curious position. "The mayor has achieved such national and international prominence," said Frank Wing, both an ally and a critic on the city council, "we have to remind him he's still a guy from the west side."

And the west side, the south side and the east side are still waiting for the full payoff from Cisneros' ambitious plans.