The privatization of Clear Channel Communications ends a 2-year effort to buyout the leading radio and outdoor advertising firm. The $17.9 billion buyout by Bain Capital and Thomas H. Lee Partners allows the new owners the opportunity to pursue strategies with less influence from unpredictable investors pursuing short-term interests. The sale comes amid heavy competition in terrestrial and satellite radio, but provides the new owners more flexibility in deciding how to best operate the 900 radio stations, radio programming services, and subsidy that owns one million outdoor ad locations. The sale is just one more in a growing trend for private equity purchases of media firms. Their interest in media companies stems from the fact that the market value of many does not reflect the underlying cash flows and asset values or the mid- to long-term prospects of the firms. The valuation challenge of media occurs in good part because advertising expenditures are not evenly distributed throughou