Currently, most of the world's shale-oil is coming from the United States, but more may be needed from non-U.S. sources in order to keep the world price of oil from increasing, and yet a number of petroleum producing countries have yet to develop shale-oil resources. This article investigates why that may be. One reason for this may be the role that shale-gas development plays in the search for shale-oil. In the oil and natural gas industry over much of the 20th century, finding oil has usually been more valuable than finding natural gas because the gas has less energy density than oil, making each BTU (or Joule) of oil energy easier to store, transport and use for consumers. However, since shale source-rock often has both natural gas and oil, then it behooves a shale search process to start by looking for natural gas first rather than oil to enhance the profitability of the search process. The problem, then, is that a shale-oil only search strategy has the same problem that first plagued the oil and gas industry: What do you do with the natural gas? In this paper, we will examine how this "chicken and egg" exploration scenario has played out in the U.S. in order to draw lessons on how dicult shale-oil development will be for the rest of the world.