The late 1940's and early 1950's brought a postwar boom and inflation to Ann Arbor. In fiscal 1949-50, the city had nearly $2 million in city improvement projects under contract, more than triple the amount of the previous year. On the University campus an eight-story dormitory--"South Quad"--was going up. It was to be the tallest "skyscraper" in the University area. In the spring of 1950 a record city budget was passed even though under its provisions all departments received less than they asked for.
Prosperity was a mixed blessing. As the city grew in size, it also grew more diverse. Diversity brought differences of opinion on the policies the city ought to adopt to insure the best possible life for its residents. Fast disappearing was the tradition of long, unbroken terms for city councilmen and members of the school board.
The most serious dispute at this time occurred between Ypsilanti and Ann Arbor over the location of the proposed new courthouse. The bond issue to finance and build it in Ann Arbor was defeated through the determined efforts of an Ypsilanti group which, understandably enough, wanted the courthouse located nearer their city. As a result construction was delayed until 1954 when the building was finally placed at Huron and Main streets in Ann Arbor.
Before television began keeping people in their living rooms, a few old-fashioned pleasures flourished a bit longer. Big time "fast-pitch" softball hit town and Veterans Park often saw crowds of 5,000 for twilight and weekend games. In 1950 Ann Arbor entrant Gerald Long placed sixth nationally in the Soap Box Derby, the best ever for the city. The Farmers' Market, long since moved from its original location when the old courthouse curb could no longer contain all the farmers and their wares, flourished and reminded everyone of the city's original intimate association with the land. And circuses still came to town, and local boys still helped to set them up.
At mid-century the University, long a nationally known institution, had increased its training facilities in engineering and the hard sciences. Its personnel brought attention to bear on national issues. During the Senator Joseph McCarthy investigation, History Professor Preston Slosson confronted Herbert J. Philipps, a communist who had been dismissed from his position as professor of philosophy at the University of Washington. They debated the merits of capitalism versus communism in a South State Street cafeteria. Two thousand people showed up for the 200 available seats.
More important, for the first time in its 130-year history Ann Arbor began to acquire a significant industrial base by the late 1950's. Much of the development was related to the great expansion of engineering and technological activities of the University, begun during the war and continued in the Cold War era. Research-oriented industry began to move into the city. In 1958 Parke Davis built a huge laboratory on the north edge of town and was soon followed by the Bendix Corporation, Conductron, Federal-Mogul, and Climax Molybdenum, among others. A research park on the south side of the city was inaugurated in 1963. In a catch phrase coined by the Ann Arbor Chamber of Commerce, the city was well on its way to becoming the "Research Center of the Midwest."
The decade of the 1950's saw the development of a vigorous two-party political system in Ann Arbor. Since the war the electorate had usually voted in excess of sixty per cent Republican. In 1953 the Republicans took all fifteen of the city's precincts. Two years later the Democrats took five of the fifteen and captured forty-six per cent of the total vote. Then in 1957 for the first time in twenty-six years, the Democrats took the mayoralty and cut the Republican council majority from 8-3 to 6-5. The 1959 city election saw the Republican recapture the mayor's post and regain their 8-3 council superiority. This seesaw pattern continued with the Democrats slowly acquiring a higher and higher percentage of the vote. In 1969 they captured the mayor's position and a council majority and in 1971 re-elected the mayor. The advent of student voting and the establishment in 1970 of a radical third party, the Human Rights Party, modified this pattern and left the city with a plurality government.
The '50's were most notable, however, for stilling the summer threnody sustained in newspaper reports of successive victims of infantile paralysis. On Monday, April 12, 1955, at 10:20 a.m., everything in Ann Arbor came to a standstill. Sixth graders at Angell Elementary School, knowing only that something big was happening, sat in uncomprehending silence as a medical report was piped over the PA into their room. Dr. Thomas Francis, Jr., professor of epidemiology at the University of Michigan School of Public Health, had directed the field testing 
The basic research had been carried out by Dr. Jonas Salk at Pittsburgh. Salk had been a student of Francis at The University of Michigan several years before. The National Foundation of Infantile Paralysis had supported the work for several years beginning in the late 1940's. All their efforts culminated in the year-long field testing program. Between April 26 and June 15, 1952, over 1,080,000 children received shots, one-third of them injected with a placebo. Throughout the summer records were kept on the characteristics of those stricken and the results tabulated and made public for the first time only as Dr. Francis spoke.
Prior to that year polio had struck up to 40,000 people each year, most of them children. Within the next seven years the disease was all but eradicated. In 1954 there were 24.8 cases per 100,000 population. By 1961 the incidence was down to 0.7 cases per 100,000.