Introduction: We were engaged to audit the financial statements of Exxon Mobil Corporation (ExxonMobil) and evaluate the effectiveness of their internal controls for the year ended December 31, 2010, in accordance with the laws of the State of Texas and the standards established by the Public Company Accounting Oversight Board (PCAOB). In the previous note sent, we highlighted the client's inherent high risk due to account balances and transactions, foreign currency conversions and the complexity of accounting and auditing of the vast oil reserves and inventories of the customer. This note will address the preliminary assessment of control risk and the appropriate level of detection risk given the previous findings on inherent risk, audit risk and control risk. Control Risk Assessment: The Internal Controls Report, according to ExxonMobil's CEO, Treasurer and Controller, states that they are solely "responsible for establishing and maintaining adequate internal control over financial reporting ( of ExxonMobil). They assessed the effectiveness of internal controls over financial reporting under the COSO framework and concluded that the controls were effective (MD&A, F-22). The Internal Controls Report recognized us, ExxonMobil's independent accounting firm PricewaterhouseCoopers LLP (PwC), stating that the company maintained effective internal control over financial reporting for 2009 and 2010, as it is management's responsibility to maintain and evaluate its effectiveness. We, PwC, are only responsible for expressing an opinion on internal controls, which we found unqualified in 2009 (MD&A, F-22). ExxonMobil did not have anything significant in 2010 that would detract from the low levels of control risk assessed by our a...... middle of paper ...... ear tip. In terms of scope, we can perform the audit without a substantially high number of samples while remaining efficient at the same time. For any questions or requests for additional information, please contact me at (202) 123-4567 or [email protected] CitedExxon Mobil Corporation Amended Form 10-K/A. (February 22, 2011). Retrieved November 20, 2011, from EDGAR Database, Exxon Mobil Corporation Financial Statements and Supplementary Information. (December 31, 2010). Retrieved November 17, 2011 from Gambrel, Jon. "Nigerian rebels seize seven oil workers". Sydney Morning Herald. Retrieved November 21, 2011 from