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                                                           Exhibit 99.302 CERT

                      State Street Research Capital Trust
                                Certification
           Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002


I, Douglas A. Romich, certify that:

1. I have reviewed this report on Form N-CSR of State Street Research Capital
Trust;

2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations, and changes in net assets of the
registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
rule 30a-2 (c) under the Investment Company Act) for the registrant and have:

     a)   designed such disclosure controls and procedures to ensure that
          material information relating to the registrant, including its
          consolidated subsidiaries, is made known to us by others within those
          entities, particularly during the period in which this report is being
          prepared;

     b)   evaluated the effectiveness of the registrant's disclosure controls
          and procedures as of the date within 90 days prior to the filing date
          of this report (the "Evaluation Date"); and

     c)   presented in this report our conclusions about the effectiveness of
          the disclosure controls and procedures based on our evaluation as of
          the Evaluation Date;

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation, to the registrant's auditors and the audit committee of
the registrant's board of directors (or persons performing the equivalent
function):

     a)   all significant deficiencies in the design or operation of internal
          controls which could adversely affect the registrant's ability to
          record, process, summarize, and report financial data and have
          identified for the registrant's auditors any material weaknesses in
          internal controls; and

     b)   any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          controls; and

6. The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Date: December 7, 2004


                                    /s/ Douglas A. Romich
                                    Douglas A. Romich
                                    Treasurer

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                      State Street Research Capital Trust
                                Certification
          Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002


I, Richard S. Davis, certify that:

1. I have reviewed this report on Form N-CSR of State Street Research
Capital Trust;

2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations, and changes in net assets of the
registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
rule 30a-2 (c) under the Investment Company Act) for the registrant and have:

     a)   designed such disclosure controls and procedures to ensure that
          material information relating to the registrant, including its
          consolidated subsidiaries, is made known to us by others within those
          entities, particularly during the period in which this report is being
          prepared;

     b)   evaluated the effectiveness of the registrant's disclosure controls
          and procedures as of the date within 90 days prior to the filing date
          of this report (the "Evaluation Date"); and

     c)   presented in this report our conclusions about the effectiveness of
          the disclosure controls and procedures based on our evaluation as of
          the Evaluation Date;

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation, to the registrant's auditors and the audit committee of
the registrant's board of directors (or persons performing the equivalent
function):

     a)   all significant deficiencies in the design or operation of internal
          controls which could adversely affect the registrant's ability to
          record, process, summarize, and report financial data and have
          identified for the registrant's auditors any material weaknesses in
          internal controls; and

     b)   any fraud, whether or not material, that involves management or other
          employees who have a significant role in the registrant's internal
          controls; and

6. The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Date: December 7, 2004


                                /s/ Richard S. Davis
                                Richard S. Davis
                                President, Chairman and Chief Executive Officer