21: PLANNING RESEARCH CORP. 1500 Planning Research Dr. McLean, Va. 22102

REVENUE: $320.7 million PROFITS: $11.4 million EARNINGS PER SHARE: $1.62 DIVIDEND: 20 cents ASSETS: $157.3 million STOCKHOLDERS' EQUITY: $65 million RETURN ON EQUITY: 17.4 percent EXCHANGE: NYSE EMPLOYES: 5,600 TOP EXECUTIVE: John M. Toups, chairman and president FOUNDED: 1954

DESCRIPTION: Planning Research could be the prototype for the dozens of "professional services" companies that have sprung up around the Beltway in recent years. It operates in a variety of fields, offering a multitude of services that include computerized real estate listings, government computer systems design and integration, and project management for government and commercial customers.

DEVELOPMENTS: Although PRC's revenue didn't grow much in 1984, its earnings did rise as it improved its operating margins. The company is counting on its largest division, PRC Government Information Systems, to provide most of its revenue growth in coming years in the form of large computer contracts from government agencies. As a step in that direction, the division won a $289 million, 18-year contract to develop and install a computer system to process patent applications for the U.S. Patent and Trademark Office.

PRC beefed up its computer systems know-how earlier this year when it announced plans to acquire Kentron International Inc., a Dallas systems-engineering firm, for $25.9 million.

PRC's Realty Systems and Systems Services divisions increased earnings in 1984, but the latter is faced with replacing declining revenue from its largest single client, the National Aeronautics and Space Administration. PRC's fourth division, its engineering unit, experienced lower revenue and earnings in fiscal 1984 as competition and the worldwide economic slump buffeted the large-scale construction products the division designs and manages.

The engineering division's problems continued to be a drag on the company through the first six months of fiscal 1985. PRC said earnings were down 44 percent in the half ended Dec. 31, as the engineering unit posted a loss in the period. 22: UNC RESOURCES INC. 7700 Leesburg Pike Falls Church, Va. 22043

REVENUE: $301 million LOSS: $122.2 million LOSS PER SHARE: $6.90 DIVIDEND: None ASSETS: $302.2 million STOCKHOLDERS' EQUITY: $137.3 million RETURN ON EQUITY: NA EXCHANGE: NYSE EMPLOYES: 4,310 TOP EXECUTIVE: Dan A. Colussy, president and chief executive officer FOUNDED: 1954

DESCRIPTION: UNC has left the uranium-mining business to concentrate on services, manufacturing and new technologies. The company's Naval Products subsidiary is one of two companies in the nation supplying nuclear fuel and reactors to power the Navy's submarines. UNC Technical Products manufactures components for defense programs, including the B-1 bomber and Trident submarine. UNC's National Automatic Tool Co. unit makes factory machinery, while UNC Nuclear Industries Inc. operates a government-owned nuclear reactor. UNC also owns a gold mine in Oregon.

DEVELOPMENTS: UNC has restructured itself radically in the last year, from a failing diversified conglomerate into a focused manufacturing and services company.

A year ago, the company was losing money, selling assets to raise cash and betting its survival on a bitter legal battle that had drained it for more than eight years. Since then, it has shed its problem businesses, won a $300 million legal settlement, selected a new chairman and chief executive, and begun looking for acquisitions in growing industries.

Last year's $122.2 million loss reflects a $119 million loss from discontinued operations, which included UNC's uranium-mining interests and its offshore products and services businesses.

The company's turning point was the settlement last May of its legal struggle with General Atomic Corp., a general partnership of Gulf Oil and Scallop Nuclear Inc. UNC's former chairman Keith A. Cunningham blamed the company's financial troubles on GAC, saying it had prevented UNC from entering into profitable long-term uranium-delivery contracts.

In the settlement, GAC agreed to pay UNC $130 million in cash and to assume $71 million of UNC's debts. Additionally, Chevron Corp., which has acquired Gulf Oil, agreed to invest $100 million in UNC by buying unissued UNC common stock. Chevron now holds 36.6 percent of UNC's stock and has two seats on its board of directors.

Cunningham retired in July at 61, leaving UNC adrift until November, when the board elected Walter S. Holmes Jr. chairman and Dan A. Colussy to become president and chief operating officer.

The company has paid down more than $70 million in bank debt and increased its working capital to $149 million, including $123 million in cash and short-term investments.

Colussy also has trimmed fat by selling the corporate building and company jet, and by cutting local staff from 100 employes to about 55. He has said he wants to acquire a well-managed company in a growing field such as telecommunications, software or aerospace.

Finally, MAXXAM Group Inc., a holding company controlled by Houston investor Charles E. Hurwitz, told the Securities and Exchange Commission last month that it has acquired 8.7 percent of UNC's stock. Earlier this year Hurwitz requested a seat on UNC's board. 23: PRESTON CORP. 151 Easton Blvd. Preston, Md. 21655

REVENUE: $299.5 million PROFITS: $8.7 million EARNINGS PER SHARE: $1.57 DIVIDEND: 50 cents ASSETS: $163 million STOCKHOLDERS' EQUITY: $99.6 million RETURN ON EQUITY: 9.2 percent EXCHANGE: OTC EMPLOYES: 4,659 TOP EXECUTIVES: A. T. Blades, chairman; Will B. Potter, president FOUNDED: 1932

DESCRIPTION: Preston Corp. is a holding company whose subsidiaries, Preston Trucking Co. Inc. and Pioneer Transportation Systems Inc., transport freight for manufacturers, retailers and wholesale distributors. Its trucking subsidiary operates over 12,000 miles along the East Coast, and has routes as far west as Missouri and Wisconsin. DEVELOPMENTS: In an effort to improve operating margins, Preston raised its rates during the first half of the fiscal year ended Dec. 31. The rate hike helped push up revenue 10 percent and profits by 30 percent over 1983. The sale of its Jersey City, N.J., facility also boosted income last year.

In January, Preston announced that it would acquire Reeves Transportation Co. of Georgia. The terms of the merger include an exchange of all the outstanding stock of Reeves for 239,450 shares of Preston's common stock. 24: THE ROUSE CO. 10275 Little Patuxent Pkwy. Columbia, Md. 21044

REVENUE: $199.1 million PROFITS: $38.6 million EARNINGS PER SHARE: $2.53 DIVIDEND: 92 cents ASSETS: $1.46 billion STOCKHOLDERS' EQUITY: $731.1 million RETURN ON EQUITY: 5.8 percent (est.) EXCHANGE: OTC EMPLOYES: 3,597 TOP EXECUTIVE: Mathias J. DeVito, president and chief executive officer FOUNDED: 1939

DESCRIPTION: Best known for its role in developing Columbia, a planned urban community between Baltimore and Washington, and for restoring Baltimore's Inner Harbor and New York's South Street Seaport, Rouse is one of the nation's leading real estate developers. The firm operates 59 shopping centers in the United States and Canada and is involved in real estate financing and insurance, as well as in urban planning.

DEVELOPMENTS: Rouse Co. successfully launched five new projects in 1984, including the refurbishing of the National Theater, which helped send profits and earnings per share skyrocketing almost 300 percent over 1983 results.

In August, Rouse sold its mortgage banking unit to Paine Webber Group Inc. for $50.5 million. Rouse Real Estate Finance Inc., under the terms of the agreement with Paine Webber, will retain its present management and will continue to be based in Columbia. The banking unit makes and services real estate loans in the Washington-Baltimore area, handling a loan portfolio of more than $2.2 billion.

The company reports that earnings from its retail centers were up 10 percent over 1983. Rouse credited the growth to increased rents and the re-leasing of almost 1.6 million square feet of existing space. Start-up losses were incurred at four new projects: South Street Seaport in New York, Gallery II in Philadelphia, Chapel Square in New Haven, Conn., and Outlet Square in Atlanta.

Locally, Rouse said business at its downtown Washington retail center, The Shops at National Place, has exceeded the company's expectations since the opening last May. Other projects completed in 1984 include The Shops at Tabor Center in downtown Denver, the Baltimore Federal Financial Center office building, expansion of The Citadel in Colorado Springs and the opening of additional stores at New York's South Street Seaport.

Another 1984 landmark for the company was record land sales at Columbia, a late 1960s joint project of Connecticut General and Rouse. The commercial properties produced earnings of $5.6 million, an increase of 28 percent over the $4.2 million recorded in 1983. 25: BDM INTERNATIONAL INC. 7915 Jones Branch Dr. McLean, Va. 22102

REVENUE: $191.4 million PROFITS: $8.1 million EARNINGS PER SHARE: $1.63 DIVIDEND: 19 cents ASSETS: $82.9 million STOCKHOLDERS' EQUITY: $39.1 million RETURN ON EQUITY: 23.2 percent EXCHANGE: Amex EMPLOYES: 2,984 TOP EXECUTIVE: Earle C. Williams, president and chief executive officer FOUNDED: 1960

DESCRIPTION: BDM International is a professional services firm that does most of its work for the U.S. military. It operates much like a think-tank, and its services range from developing and testing a laser weapon for the Army and building the world's largest solar-electric plant to studying how to bring better health care to rural children.

DEVELOPMENTS: BDM reported a 30 percent gain in revenue, profits and earnings per share for the fiscal year ended Dec. 31 -- results consistent with its annual growth rate of approximately 30 percent for the past 15 years. BDM attributed that record to its ability to compete effectively for government contracts of all sizes.

BDM received its largest single contract to date this January, a $100 million, 10-year deal with the U.S. Air Force to develop and establish a data bank to support Air Force weapons systems.

The company said it commenced, continued or concluded almost 700 contracts in 1984, for a wide variety of government defense agencies. It also said it expanded its seven-year participation in the U.S. Ballistic Missile Defense Program. The company reported that it received contracts in several new areas, including lasers and directed-energy weapons, artificial intelligence, strategic computing and fiber optics.