Nearly 70 years ago, Joseph A. Bank formed a partnership with his mother-in-law to make and sell men's clothing. Today, the legacy of that venture includes a chain of 12 discount retail stores and a national mail-order business.

Jos. A. Bank Clothiers' President Leonard Ginsberg, who has been with the firm since 1946, observed: "When I first came here, sales were around $400,000. Ten years ago, they reached $6 million, and they'll probably be 10 times that by the end of this fiscal year."

Bank's success has always been carefully orchestrated, especially by the handful of family members who owned and operated the privately held company. It has maintained a presence in Washington since the late 1940s, when Howard Bank, the son of the founder, bought a part interest in Louis's Inc., a popular men's clothing establishment at 633 D St. NW.

In the mid-50s, Bank acquired full interest in the firm. In 1969 the store began trading as Joseph A. Bank at a location on 18th Street. It now has three outlets in the Washington area--at 1118 19th St. NW, White Flint Plaza and Loehmann's Plaza.

Last July 1, Bank became a wholly owned subsidiary of Quaker Oats, a $2.6 billion conglomerate. No one involved will divulge specific information about the deal, but Robert B. Bank, son of the late Howard Bank and grandson of the founder, observed, "Suffice it to say, it benefitted the family and helped with some estate problems."

The vice president for merchandising then volunteered: "So far, there has been absolutely no change in the way we operate."

Bank, a Princeton graduate who holds a master's degree in American history from Johns Hopkins University, is sure that he and his colleagues will continue to have full autonomy. "Quaker Oats knows that we've run this business well for years, so they're not going to come in and make major changes," he said.

The parent company has diversified widely over the past 15 years. Its holdings include Fisher-Price toys, Ken-L Ration, Celeste pizza and Magic Pan restaurants. According to Clinton Mayer, a food industry analyst at Bear, Stearns and Co. in New York, Bank fits neatly into Quaker's corporate strategy.

Bank has three retail stores in the Baltimore area, two in Philadelphia and single outlets in Atlanta, Charlotte and Richmond. It opened its 12th store last August in Wilmette, along Chicago's affluent north shore.

"Sales in Wilmette the first month were double our most optimistic forecasts," Rand observed. "Consequently, we decided that Chicagoans already knew a great deal about Bank through its catalogue and swamped the store when it opened."

Quaker Oats intends to continue capitalizing on Bank's extensive catalogue business by opening more retail stores. Rand said, "we plan to provide Bank with increased capital for them to expand."

Bank President Ginsberg, who is the son-in-law of the store's founder, is more specific. "We will open our 13th store next March in Boston. Then we plan to open two a year for the next several years." Possible sites include another store in Chicago, as well as entry into Dallas, Detroit, Houston, New York and St. Louis.

With retail store sales accounting for 70 percent of Bank's business, it is not surprising that this segment of operations will continue to receive major attention. Catalogue sales will also be emphasized. Not only do mail orders make up 21 percent of total sales, but they are often linked to retail outlets.

In its headquarters three blocks east of Baltimore's World Trade Center and in another plant northeast of the city at Hampstead, Joseph A. Bank makes half of everything it sells retail. On the average, the company sells these goods for 30 percent less than other high-quality stores. Discounts average 20 percent for goods not manufactured by Bank.

Bank maintains no wholesale sales force, and sales in this category represent only 9 percent of the total. Bank makes, and sells wholesale, only one major men's and one women's line of clothes. "There is no way that you'd know we made the garments," merchandising Vice President Robert B. Bank pointed out. "It has somebody else's name." He won't divulge what the brands are, but he added, "each is a name you'd see and recognize at any major department store." ince Bank was privately owned by family members until last July, specific financial data were not required to be made public. Because the firm is now a wholly owned subsidiary of Quaker Oats, that rule still applies. Company officials, however, will divulge some information.

For example, more than 900 of Bank's 1,146 employes are engaged in manufacturing and retail sales. Ninety-one percent of Bank's volume is at the retail level, with one-fifth derived from women's clothes.

Each week, Bank makes 4,000 coats, 4,500 pairs of pants, 1,500 skirts and 500 vests in its manufacturing facilities at Baltimore and Hampstead. The company also has begun making dresses.

"We feel that we're positioned very attractively, in terms of the markets we reach," concluded Stephen A. Bank, executive vice president in charge of the catalogue division. "Our clothes are conservative and preppy and are very attractive pricewise. We're aiming at metropolitan areas, especially that portion of the market with a conservative bias."

Bank surveys show that their average catalogue customer has some graduate or professional training, with an income skewed toward the higher side.

With a tenfold increase in sales over the past decade, Joseph A. Bank obviously has been making the right decisions. Robert B. Bank succinctly described his firm's method of operation. "Since I came here a little over 10 years ago, we've become vertically integrated, which means we've been able to eliminate certain distribution stages. And that obviously keeps our costs down."

While Robert Bank's late father, Howard, emphasized manufacturing, the younger Bank has directed his attention primarily to retailing.

"In selecting our retail sites, for example, we insist on minimizing costs. We follow other high-quality stores into an area, but we locate nearby, not in the most expensive mall, where they are." Bank has followed that practice in the Washington area, with its locations in White Flint and Loehmann's Plaza, which are not in the highest priced, prime space.

Expansion plays a major role in Bank's future. So does further emphasis on women's clothes. Heretofore, Bank has transferred its men's styles to its women's line. And, at sales that will soon reach $12 million, its women's division's sales are double total sales just 10 years ago. But Robert Bank says that today's professional women will not tolerate styles that are carbon copies of men's. "We're beginning to add bows, silks, more style to the basic Oxford and tweed for women," he concluded.

Jos. A. Bank Clothiers long ago outgrew its Ma and Pa clothing shop status in downtown Baltimore. However, the Bank family, which also includes active vice presidents Harriet and Raymond Bank, Robert and Stephen Bank's mother and brother, will not allow it to become too big for its breeches.