Both tax administrations and taxpayers often have difficulty in obtaining adequate information to apply the arm’s length principle. Because the arm’s length principle usually requires taxpayers and tax administrations to evaluate uncontrolled transactions and the business activities of independent enterprises, and to compare these with the transactions and activities of associated enterprises, it can demand a substantial amount of data. The information that is accessible may be incomplete and difficult to interpret; other information, if it exists, may be difficult to obtain for reasons of its geographical location or that of the parties from whom it may have to be acquired. In addition, it may not be possible to obtain information from independent enterprises because of confidentiality concerns. In other cases information about an independent enterprise which could be relevant may simply not exist, or there may be no comparable independent enterprises, e.g. if that industry has reached a high level of vertical integration. It is important not to lose sight of the objective to find a reasonable estimate of an arm’s length outcome based on reliable information. It should also be recalled at this point that transfer pricing is not an exact science but does require the exercise of judgment on the part of both the tax administration and taxpayer.