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</LabelSeparator><Level>2</Level><ElementName>us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock</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><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="D2013Q2YTD" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font-family:Times New Roman;font-size:10pt;"&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;font-weight:bold;"&gt;Description of Business and Basis of Presentation &lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;padding-left:24px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;American CareSource Holdings, Inc. (&amp;#8220;ACS,&amp;#8221; &amp;#8220;Company,&amp;#8221;&amp;#160;the &amp;#8220;Registrant,&amp;#8221; &amp;#8220;we,&amp;#8221; &amp;#8220;us,&amp;#8221; or &amp;#8220;our&amp;#8221;) works to help its clients control healthcare costs by offering cost containment strategies, primarily through the utilization of a comprehensive national network of ancillary healthcare service providers.&amp;#160;&amp;#160;The Company markets its services to a number of healthcare companies including third party administrators (&amp;#8220;TPAs&amp;#8221;), insurance companies, large self-funded organizations, various employer groups and preferred provider organizations ("PPOs").&amp;#160;&amp;#160;The Company offers payors this solution by:&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;/font&gt;&lt;/div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:48px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:24px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8226;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;lowering its payors&amp;#8217; ancillary care costs through its network of high quality, cost effective providers that the Company has under contract at more favorable terms than they could generally obtain on their own;&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:48px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:24px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8226;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;providing payors with a comprehensive network of ancillary healthcare service providers that is tailored to each payor&amp;#8217;s specific needs and is available to each payor&amp;#8217;s members for covered services;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:48px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:24px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8226;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;providing payors with claims management, reporting and processing and payment services;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;padding-left:4px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:48px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:24px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8226;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;performing network/needs analysis to assess the benefits to payors of adding additional/different service providers to the payor-specific provider networks; and&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;padding-left:4px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"&gt;&lt;tr&gt;&lt;td style="width:48px;" rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;td rowspan="1" colspan="1"&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td style="vertical-align:top" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;padding-left:24px;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#8226;&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="vertical-align:top;" rowspan="1" colspan="1"&gt;&lt;div style="line-height:120%;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;credentialing network service providers for inclusion in the payor-specific provider networks.&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (&amp;#8220;GAAP&amp;#8221;), interim reporting requirements of Form 10-Q and Rule 8-03 of Regulation S-X of the rules and regulations of the Securities and Exchange Commission (&amp;#8220;SEC&amp;#8221;).&amp;#160;&amp;#160;Consequently, financial information and disclosures normally included in financial statements prepared annually in accordance with GAAP have been condensed or omitted.&amp;#160;&amp;#160;Balance sheet amounts are as of &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;December&amp;#160;31, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and operating results are for the  &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;three and six&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; months ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;June&amp;#160;30, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt; and &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, and include all normal and recurring adjustments we consider necessary for the fair, summarized presentation of our financial position and operating results.  Certain prior year amounts have been reclassified within the consolidated statement of operations to conform to the current year presentation.&amp;#160;&amp;#160;As these are condensed financial statements, readers of this report should, therefore, refer to the consolidated financial statements and the notes included in our Annual Report on Form 10-K for the fiscal year ended &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;December&amp;#160;31, 2012&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;, filed with the SEC on &lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;color:#000000;text-decoration:none;"&gt;March&amp;#160;4, 2013&lt;/font&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;The Company uses the &amp;#8220;management approach&amp;#8221; for reporting information about segments in annual and interim financial statements.&amp;#160;&amp;#160;The management approach is based on the way the chief operating decision-maker organizes segments within a company for making operating decisions and assessing performance.&amp;#160;&amp;#160;Reportable segments are based on products and services, geography, legal structure, management structure and any other manner in which management disaggregates a company.&amp;#160;&amp;#160;Based on the &amp;#8220;management approach&amp;#8221; model, the Company has determined that its business is comprised of a single operating segment.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;padding-left:36px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&amp;#160;&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;text-indent:48px;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;Our interim results of operations are not necessarily indicative of results of operations that will be realized for the full fiscal year.&lt;/font&gt;&lt;/div&gt;&lt;div style="line-height:120%;text-align:justify;font-size:10pt;"&gt;&lt;font style="font-family:inherit;font-size:10pt;"&gt;&lt;br clear="none"/&gt;&lt;/font&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the business description and basis of presentation concepts.  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