Why firms adhere to or deviate from their strategic plans is poorly understood. However, theory and limited research suggest that the process through which such plans emerge may play a part. In particular, top management decision-sharing consensus-oriented, team-based Decision -making-may increase the likelihood that firms will adhere to their plans, because those involved in the decision-making may be more committed to the chosen course of action, thereby increasing the likelihood that organizations will subsequently adhere to their plans.

    However, the relationship between top management decision-sharing and adherence to plans may be affected by a firm's strategic mission (its fundamental approach to increasing sales revenue and market share, and generating cash flow and short-term profits). At one end of the strategic mission continuum, "build" strategies are pursued when a firm desires to increase its market share and is willing to sacrifice short-term profits to do so. At the other end, "harvest" strategies are used when a firm is willing to sacrifice market share for short-term profitability and cash-flow maximization. Research and theory suggest that top management decision-sharing may have a more positive relationship with adherence to plans among firms with harvest strategies than among firms with build strategies. In a study of strategic practices in several largefirms, managers in harvest strategy scenarios were more able to adhere to their business plans. As one of the managers in the study explained it, this is partly because "[t] ypically all a manager has to do [when implementing a harvest strategy] is that which was done last year." Additionally, managers under harvest strategies may have fewer strategic options than do those under build strategies; it may therefore be easier to reach agreement on a particular course of action through decision-sharing, which will in turn tend to promote adherence to plans. Conversely, in a "build" strategy scenario, individual leader-ship, rather than decision-sharing, may promote adherence to plans. Build strategies-which typically require leaders with strong personal visions for a firm's future, rather than the negotiated compromise of the team-based decision-maybe most closely adhered to when implemented in the context of a clear strategic vision of an individual leader, rather than through the practice of decision-sharing.

    Findings from several studies on corporate mergers and acquisitions during the 1970's and 1980's raise questions about why firms initiate and consummate such transactions. One study showed, for example, that acquiring firms were on average unable to maintain acquired firms' pre-merger levels of profitability. A second study concluded that post-acquisition gains to most acquiring firms were not adequate to cover the premiums paid to obtain acquired firms. A third demonstrated that, following the announcement of a prospective merger, the stock of the prospective acquiring firm tends to increase in value much less than does that of the firm for which it bids. Yet mergers and acquisitions remain common, and bidders continue to assert that their objectives are economic ones. Acquisitions may well have the desirable effect of channeling a nation's resources efficiently from less to more efficient sectors of its economy, but the individual acquisitions executives arranging these deals must see them as advancing either their own or their companies' private economic interests. It seems that factors having little to do with corporate economic interests explain acquisitions. These factors may include the incentive compensation of executives, lack of monitoring by boards of directors, and managerial error in estimating the value of firms targeted for acquisition. Alternatively, the acquisition acts of bidders may derive from modeling: a manager does what other managers do.

    In 1975 Chinese survey teams remeasured Mount Everest, the highest of the Himalayan mountains. Like the British in 1852, they used the age-old technique of "carrying in" sea level: surveyors marched inland from the coast for thousands of miles, stopping at increments of as little as a few feet to measure their elevation, and marking each increment with two poles. To measure the difference in elevation between poles, surveyors used an optical level—a telescope on a level base—placed halfway between the poles. They sighted each pole, reading off measurements that were then used to calculate the change in eleva tion over each increment. In sight of the peaks the used theodolites—telescopes for measuring vertical and horizontal angles—to determine the elevation of the summit.

    The Chinese, however, made efforts to correct for the errors that had plagued the British. One source of error is refraction, the bending of light beams as they pass through air layers of different temperature and pressure. Because light traveling. down from a summit passes through many such layers, a surveyor could sight a mirage rather than the peak itself. To reduce refraction errors, the Chinese team carried in sea level to within five to twelve miles of Everest's summit, decreasing the amount of air that light passed through on its way to their theodolites. The Chinese also launched weather balloons near their theodolites to measure atmospheric temperature and pressure changes to better estimate refraction errors. Another hurdle is the peak's shape. When surveyors sight the summit. there is a risk they might not all measure the same point. In 1975 the Chinese installed the first survey beacon on Everest, a red reflector visible through a theodolite for ten miles, as a reference point. One more source of error is the unevenness of sea level. The British assumed that carrying in sea level would extend an imaginary line from the shore along Earth's curve to a point beneath the Himalaya. In reality, sea level varies according to the irregular interior of the planet. The Chinese used a gravity meter to correct for local deviations in sea level.

    In 1994, a team of scientists led by David Mckay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001,the first ever found in Martian rock. Organic molecules-complex, carbon based compounds-form the basis for terrestrial life. The organic molecules found in ALH84001 are polycyclic aromatic hydrocarbons, or PAH's. When microbes die, their organic material often decays into PAH's.

    Skepticism about the McKay team's claim remains, however. For example,ALH84001 has been on earth for 13,000 years, suggesting to some scientists that its PAH's might have resulted from terrestrial contamination. However, McKay's team has demonstrated that the concentration of PAH's increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptic's strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay' steam, including PAH's. For example, star formation produces PAH's. Moreover, PAH's frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay's team notes that the particular combination of PAH's in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating form nonbiological processes.