Cell phone towers derive revenue from multiple tenants who use the infrastructure simultaneously. Because of the regulatory difficulty of building new towers (at least domestically), growth is largely driven by adding tenants to existing towers. This gives the tower companies significant barriers to entry and strong cash flow from incremental business at each tower.

The company's fortunes depend on the success of the wireless communications business. The industry grew 38% growth from 2004 to 2006,^[2] driven by greater market saturation and higher levels of cell phones per user and per household. As the US wireless market matures with a penetration near 75%^[3], growth domestically will eventually slow and likely be dependent on higher cell phones per capita as well as incremental subscriber airtime. The company had no international operations as of the end of 2006, giving its competitors a head start in capitalizing on emerging cell phone markets. Furthermore, it is only about 50% exposed to the most quickly growing regions of the US, compared to about 70% for its competitors.

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