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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>verboseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="Context_FYE_31-Mar-2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="line-height: normal; margin-bottom: 0pt;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;1.&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&lt;u&gt;Organization&lt;/u&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="line-height: normal; margin-bottom: 0pt;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;Boston Financial Tax Credit Fund VIII, A Limited Partnership (the "Fund") is a Massachusetts limited partnership organized to invest in other limited partnerships or limited liability companies (collectively, "Local Limited Partnerships") which own and operate apartment complexes (each, a &amp;#8220;Property&amp;#8221;) which are eligible for low income housing tax credits (&amp;#8220;Tax Credits&amp;#8221;) that may be applied against the federal income tax liability of an investor. The Fund&amp;#8217;s objectives are to: (i) provide investors with annual Tax Credits which they may use to reduce their federal income tax liability; (ii) preserve and protect the Fund&amp;#8217;s capital; (iii) provide cash distributions from the operations of Local Limited Partnerships; and(iv) providecash distributions from sale or refinancing transactions.&amp;#160;&amp;#160;Arch Street VIII Limited Partnership ("Arch Street L.P."), a Massachusetts limited partnership consisting of Arch Street VIII, Inc., a Massachusetts corporation ("Arch Street, Inc.") as the sole general partner, ALZA Corporation as Class A limited partner (90%) and Boston Financial BFG Investments, LLC, as Class B limited partner (9%), is the sole General Partner of the Fund. Arch Street L.P. and Arch Street, Inc. are affiliates of Boston Financial Investment Management, LP (&amp;#8220;Boston Financial&amp;#8221;).&amp;#160;&amp;#160;The fiscal year of the Fund ends on March 31.&lt;/font&gt;&lt;/p&gt;
&lt;p style="line-height: normal; margin-bottom: 0pt;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;The Partnership Agreement authorizes the sale of up to 200,000 units of limited partnership interest ("Units") at $1,000 per Unit in series.&amp;#160;&amp;#160;The first series offered 50,000 Units.&amp;#160;&amp;#160;On August 31, 1994, the Fund held its final investor closing.&amp;#160;&amp;#160;In total, the Fund received $36,497,000 of capital contributions from investors admitted as Limited Partners, for a total of 36,497 Units.&lt;/font&gt;&lt;/p&gt;
&lt;p style="line-height: normal; margin-bottom: 0pt;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;The General Partner initially designated 5% of the Gross Proceeds as Reserves, as defined in the Partnership Agreement.&amp;#160;&amp;#160;The Reserves were established to be used for working capital of the Fund and contingencies related to the ownership of Local Limited Partnership interests.&amp;#160;&amp;#160;The General Partner may increase or decrease such Reserves, from time to time, as it deems appropriate.&amp;#160;&amp;#160;At March 31, 2013 and 2012, approximately $604,000 and $37,000 respectively, has been designated as Reserves.&lt;/font&gt;&lt;/p&gt;
&lt;p style="line-height: normal; margin-bottom: 0pt;" class="msonormal"&gt;&lt;font size="2" style="font-family:times new roman,times"&gt;Generally, profits, losses, tax credits and cash flows from operations are allocated 99% to the Limited Partners and 1% to the General Partner.&amp;#160;&amp;#160;Net proceeds from a sale of the Fund&amp;#8217;s interest in a Local Limited Partnership or refinancing of a Local Limited Partnership&amp;#8217;s debt will be allocated 95% to the Limited Partners and 5% to the General Partner, after certain priority payments.&amp;#160;&amp;#160;&amp;#160;The General Partner may have an obligation to fund deficits in its capital accounts, subject to limits set forth in the Partnership Agreement.&amp;#160;&amp;#160;However, to the extent that the General Partner&amp;#8217;s capital accounts are in a deficit position, certain items of net income may be allocated to the General Partner in accordance with the Partnership Agreement.&lt;/font&gt;&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>The entire disclosure for the business description and basis of presentation concepts.  Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity.  Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Business Description and Basis of Presentation [Text Block]</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Organization</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.bostonfinancial.com/role/Organization</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
