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      <filer>
        <filerCredentials>
          <cik>0001032235</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001013857</issuerCik>
      <issuerName>PEGASYSTEMS INC</issuerName>
      <secFileNumber>001-11859</secFileNumber>
      <issuerAddress>
        <com:street1>ONE MAIN STREET</com:street1>
        <com:city>CAMBRIDGE</com:city>
        <com:stateOrCountry>MA</com:stateOrCountry>
        <com:zipCode>02142-1531</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>6173749600</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>TREFLER ALAN</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
        <relationshipToIssuer>10% Stockholder</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Wells Fargo Clearing Services</name>
        <address>
          <com:street1>1 N. Jefferson Ave.</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63103</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>30000</noOfUnitsSold>
      <aggregateMarketValue>2076950.89</aggregateMarketValue>
      <noOfUnitsOutstanding>85409645</noOfUnitsOutstanding>
      <approxSaleDate>08/15/2024</approxSaleDate>
      <securitiesExchangeName>Nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/20/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Gift</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Alan Trefler</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>Y</isGiftTransaction>
      <donarAcquiredDate>05/08/1997</donarAcquiredDate>
      <amountOfSecuritiesAcquired>30000</amountOfSecuritiesAcquired>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Pamela Trefler</name>
        <address>
          <com:street1>ONE MAIN STREET</com:street1>
          <com:city>CAMBRIDGE</com:city>
          <com:stateOrCountry>MA</com:stateOrCountry>
          <com:zipCode>02142-1531</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common Shares of PEGA</securitiesClassTitle>
      <saleDate>08/05/2024</saleDate>
      <amountOfSecuritiesSold>1000</amountOfSecuritiesSold>
      <grossProceeds>65246.18</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>Shares were in the account of the Trefler Foundation, Alan Trefler is on the foundation account and is an Officer and 10 percent shareholder of PEGA.</remarks>
    <noticeSignature>
      <noticeDate>08/15/2024</noticeDate>
      <signature>Alan Trefler</signature>
    </noticeSignature>
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144
0001032235
XXXXXXXX
LIVE
0001013857
PEGASYSTEMS INC
001-11859
ONE MAIN STREET
CAMBRIDGE
MA
02142-1531
6173749600
TREFLER ALAN
Officer
10% Stockholder
Common
Wells Fargo Clearing Services
1 N. Jefferson Ave.
St. Louis
MO
63103
30000
2076950.89
85409645
08/15/2024
Nasdaq
Common
12/20/2023
Gift
Alan Trefler
Y
05/08/1997
30000
N/A
N
Pamela Trefler
ONE MAIN STREET
CAMBRIDGE
MA
02142-1531
Common Shares of PEGA
08/05/2024
1000
65246.18
Shares were in the account of the Trefler Foundation, Alan Trefler is on the foundation account and is an Officer and 10 percent shareholder of PEGA.
08/15/2024
Alan Trefler