﻿<?xml version="1.0" encoding="utf-8"?>
<InstanceReport xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Version>2.2.0.7</Version>
  <hasSegments>false</hasSegments>
  <ReportName>ACQUISITIONS</ReportName>
  <ReportLongName>10601 - Disclosure - ACQUISITIONS</ReportLongName>
  <DisplayLabelColumn>true</DisplayLabelColumn>
  <ShowElementNames>false</ShowElementNames>
  <RoundingOption />
  <HasEmbeddedReports>false</HasEmbeddedReports>
  <Columns>
    <Column>
      <LabelColumn>false</LabelColumn>
      <Id>1</Id>
      <Labels>
        <Label Id="1" Label="9 Months Ended" />
        <Label Id="2" Label="Sep. 30, 2010" />
      </Labels>
      <CurrencyCode>USD</CurrencyCode>
      <FootnoteIndexer />
      <hasSegments>false</hasSegments>
      <hasScenarios>false</hasScenarios>
      <Segments />
      <Scenarios />
      <Units>
        <Unit>
          <UnitID>Unit12</UnitID>
          <UnitType>Standard</UnitType>
          <StandardMeasure>
            <MeasureSchema>http://www.xbrl.org/2003/iso4217</MeasureSchema>
            <MeasureValue>USD</MeasureValue>
            <MeasureNamespace>iso4217</MeasureNamespace>
          </StandardMeasure>
          <Scale>0</Scale>
        </Unit>
        <Unit>
          <UnitID>Unit13</UnitID>
          <UnitType>Divide</UnitType>
          <NumeratorMeasure>
            <MeasureSchema>http://www.xbrl.org/2003/iso4217</MeasureSchema>
            <MeasureValue>USD</MeasureValue>
            <MeasureNamespace>iso4217</MeasureNamespace>
          </NumeratorMeasure>
          <DenominatorMeasure>
            <MeasureSchema>http://www.xbrl.org/2003/instance</MeasureSchema>
            <MeasureValue>shares</MeasureValue>
            <MeasureNamespace>xbrli</MeasureNamespace>
          </DenominatorMeasure>
          <Scale>0</Scale>
        </Unit>
      </Units>
      <CurrencySymbol>$</CurrencySymbol>
    </Column>
  </Columns>
  <Rows>
    <Row>
      <Id>2</Id>
      <Label>ACQUISITIONS</Label>
      <Level>0</Level>
      <ElementName>wso_AcquisitionsAbstract</ElementName>
      <ElementPrefix>wso</ElementPrefix>
      <IsBaseElement>false</IsBaseElement>
      <BalanceType>na</BalanceType>
      <PeriodType>duration</PeriodType>
      <ShortDefinition>Acquisitions [Abstract]</ShortDefinition>
      <IsReportTitle>false</IsReportTitle>
      <IsSegmentTitle>false</IsSegmentTitle>
      <IsSubReportEnd>false</IsSubReportEnd>
      <IsCalendarTitle>false</IsCalendarTitle>
      <IsTuple>false</IsTuple>
      <IsAbstractGroupTitle>true</IsAbstractGroupTitle>
      <IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow>
      <IsEquityAdjustmentRow>false</IsEquityAdjustmentRow>
      <IsBeginningBalance>false</IsBeginningBalance>
      <IsEndingBalance>false</IsEndingBalance>
      <IsReverseSign>false</IsReverseSign>
      <PreferredLabelRole />
      <IsEPS>false</IsEPS>
      <FootnoteIndexer />
      <Cells>
        <Cell>
          <Id>1</Id>
          <ShowCurrencySymbol>false</ShowCurrencySymbol>
          <IsNumeric>false</IsNumeric>
          <IsRatio>false</IsRatio>
          <DisplayZeroAsNone>false</DisplayZeroAsNone>
          <NumericAmount>0</NumericAmount>
          <RoundedNumericAmount>0</RoundedNumericAmount>
          <NonNumbericText />
          <NonNumericTextHeader />
          <FootnoteIndexer />
          <hasSegments>false</hasSegments>
          <hasScenarios>false</hasScenarios>
          <DisplayDateInUSFormat>false</DisplayDateInUSFormat>
        </Cell>
      </Cells>
      <OriginalInstanceReportColumns />
      <ElementDataType>xbrli:stringItemType</ElementDataType>
      <SimpleDataType>string</SimpleDataType>
      <ElementDefenition>Acquisitions [Abstract]</ElementDefenition>
      <IsTotalLabel>false</IsTotalLabel>
    </Row>
    <Row>
      <Id>3</Id>
      <Label>ACQUISITIONS</Label>
      <Level>1</Level>
      <ElementName>us-gaap_BusinessCombinationDisclosureTextBlock</ElementName>
      <ElementPrefix>us-gaap</ElementPrefix>
      <IsBaseElement>true</IsBaseElement>
      <BalanceType>na</BalanceType>
      <PeriodType>duration</PeriodType>
      <ShortDefinition>No definition available.</ShortDefinition>
      <IsReportTitle>false</IsReportTitle>
      <IsSegmentTitle>false</IsSegmentTitle>
      <IsSubReportEnd>false</IsSubReportEnd>
      <IsCalendarTitle>false</IsCalendarTitle>
      <IsTuple>false</IsTuple>
      <IsAbstractGroupTitle>false</IsAbstractGroupTitle>
      <IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow>
      <IsEquityAdjustmentRow>false</IsEquityAdjustmentRow>
      <IsBeginningBalance>false</IsBeginningBalance>
      <IsEndingBalance>false</IsEndingBalance>
      <IsReverseSign>false</IsReverseSign>
      <PreferredLabelRole>terselabel</PreferredLabelRole>
      <IsEPS>false</IsEPS>
      <FootnoteIndexer />
      <Cells>
        <Cell>
          <Id>1</Id>
          <ShowCurrencySymbol>false</ShowCurrencySymbol>
          <IsNumeric>false</IsNumeric>
          <IsRatio>false</IsRatio>
          <DisplayZeroAsNone>false</DisplayZeroAsNone>
          <NumericAmount>0</NumericAmount>
          <RoundedNumericAmount>0</RoundedNumericAmount>
          <NonNumbericText>&lt;div&gt;
&lt;table style="border-collapse: collapse;" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;&lt;td valign="top" width="4%" align="left"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;6.&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;ACQUISITIONS &lt;/b&gt;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
&lt;p style="margin-top: 6px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;In April 2010, one of our wholly-owned subsidiaries acquired certain assets and assumed certain liabilities of a wholesale distributor of air conditioning and heating products operating from two locations in Tennessee for cash consideration of approximately $2,400. &lt;/font&gt;&lt;/p&gt;
&lt;p style="margin-top: 12px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;In August 2009, one of our wholly-owned subsidiaries acquired certain assets and assumed certain liabilities of a wholesale distributor of air conditioning and heating products operating from six locations in Utah and serving over 500 customers for cash consideration of $4,057, net of cash acquired. &lt;/font&gt;&lt;/p&gt;
&lt;p style="margin-top: 12px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;In July 2009, we completed the formation of Carrier Enterprise, LLC ("Carrier Enterprise"), which is a joint venture between us and Carrier Corporation ("Carrier"). Carrier contributed to Carrier Enterprise 95 locations in the U.S. Sunbelt and Puerto Rico and Carrier's export division located in Miami, Florida, and we contributed 15 locations that distributed Carrier products. We purchased a 60% controlling interest in the joint venture for a fair value of $181,474 with options to purchase up to an additional 20% interest from Carrier (10% beginning in July 2012 and an additional 10% in July 2014). Total consideration paid by us for our 60% controlling interest in Carrier Enterprise was composed of our issuance to Carrier of 2,985,685 shares of Common stock and 94,784 shares of Class B common stock having a fair value of $151,056 and our contribution of 15 locations that sold Carrier-manufactured products valued at $25,000. The final purchase price was subject to $5,418 of working capital adjustments pursuant to the Purchase and Contribution Agreement dated May&amp;nbsp;3, 2009, as amended June&amp;nbsp;29, 2009, ("Purchase and Contribution Agreement") and was completed during the fourth quarter of 2009. The results of operations of these acquired locations have been included in our condensed consolidated unaudited financial statements from their respective dates of acquisition. The pro forma effect of the April 2010 and August 2009 acquisitions were not deemed significant to the condensed consolidated unaudited financial statements. &lt;/font&gt;&lt;/p&gt;
&lt;p style="margin-top: 12px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Acquisition-related costs of $2,503 and $3,833 were included in selling, general and administrative expenses in our condensed consolidated unaudited statements of income for the quarter and nine months ended September&amp;nbsp;30, 2009, respectively. &lt;/font&gt;&lt;/p&gt; &lt;/div&gt;</NonNumbericText>
          <NonNumericTextHeader>6.
ACQUISITIONS
In April 2010, one of our wholly-owned subsidiaries acquired certain assets and assumed certain liabilities of a wholesale distributor of air</NonNumericTextHeader>
          <FootnoteIndexer />
          <hasSegments>false</hasSegments>
          <hasScenarios>false</hasScenarios>
          <DisplayDateInUSFormat>false</DisplayDateInUSFormat>
        </Cell>
      </Cells>
      <OriginalInstanceReportColumns />
      <ElementDataType>us-types:textBlockItemType</ElementDataType>
      <SimpleDataType>textblock</SimpleDataType>
      <ElementDefenition>Description of a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. This element may be used as a single block of text to encapsulate the entire disclosure (including data and tables) regarding business combinations, including leverage buyout transactions (as applicable).</ElementDefenition>
      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141
 -Paragraph 51, 52

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Emerging Issues Task Force (EITF)
 -Number 88-16

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph 67-73

Reference 4: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph F4
 -Subparagraph e
 -Appendix F

</ElementReferences>
      <IsTotalLabel>false</IsTotalLabel>
    </Row>
  </Rows>
  <Footnotes />
  <NumberOfCols>1</NumberOfCols>
  <NumberOfRows>2</NumberOfRows>
  <HasScenarios>false</HasScenarios>
  <MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel>
  <SharesRoundingLevel>UnKnown</SharesRoundingLevel>
  <PerShareRoundingLevel>UnKnown</PerShareRoundingLevel>
  <HasPureData>false</HasPureData>
  <SharesShouldBeRounded>true</SharesShouldBeRounded>
</InstanceReport>
