<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>000110 - Disclosure - Note 5. Going Concern</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>us-gaap_LiquidityDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D110601_120531" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;!--egx--&gt;&lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;NOTE 5. GOING CONCERN&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;The accompanying financial statements have been prepared assuming that the Company will continue as a going concern. The Company has net losses for the period from inception (December 20, 2007) to May 31, 2012. This condition raises substantial doubt about the Company&amp;#146;s ability to continue as a going concern. The Comnpany has negative working capital and has no cash. The Company&amp;#146;s continuation as a going concern is dependent on its ability to meet its obligations, to obtain additional financing as may be required and ultimately to attain profitability. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;&amp;nbsp;&lt;/p&gt; &lt;p style='margin:0in;margin-bottom:.0001pt;text-align:justify'&gt;Management is planning to raise additional funds through debt or equity offerings. There is no guarantee that the Company will be successful in these efforts. There is no guarantee that the Company will be successful generating profits from its oil and gas operations.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>Disclosure of accounting policy for reporting when there is a substantial doubt about an entity's ability to continue as a going concern for a reasonable period of time (generally a year from the balance sheet date). Disclose: (a) pertinent conditions and events giving rise to the assessment of substantial doubt about the entity's ability to continue as a going concern for a reasonable period of time, (b) the possible effects of such conditions and events, (c) management's evaluation of the significance of those conditions and events and any mitigating factors, (d) possible discontinuance of operations, (e) management's plans (including relevant prospective financial information), and (f) information about the recoverability or classification of recorded asset amounts or the amounts or classification of liabilities. If management's plans alleviate the substantial doubt about the entity's ability to continue as a going concern, disclosure of the principal conditions and events that initially raised the substantial doubt about the entity's ability to continue as a going concern would be expected to be considered. Disclose whether operations for the current or prior years generated sufficient cash to cover current obligations, whether waivers were obtained from creditors relating to the company's default under the provisions of debt agreements and possible effects of such conditions and events, such as: whether there is a possible need to obtain additional financing (debt or equity) or to liquidate certain holdings to offset future cash flow deficiencies. Disclose appropriate parent company information when parent is dependent upon remittances from subsidiaries to satisfy its obligations.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Note 5. Going Concern</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Note 5. 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