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                                                                    Exhibit 31.2

   I, Timothy C. O'Brien, Chief Financial Officer of Lightbridge, Inc., certify
            that:

   1. I have reviewed this annual report on Form 10-K of Lightbridge, Inc.;

   2. Based on my knowledge, this annual 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 cash
            flows 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 Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal
            control over financial reporting (as defined in Exchange Act Rules
            13a-15(f) and 15d-15(f)) for the registrant and have:

            a) Designed such disclosure controls and procedures to ensure, or
               caused such disclosure controls and procedures to be designed
               under our supervision, 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) Designed such internal control over financial reporting, or
               caused such internal control over financial reporting to be
               designed under our supervision, to provide reasonable assurance
               regarding the reliability of financial reporting and the
               preparation of financial statements for external purposes in
               accordance with generally accepted accounting principles;

            c) Evaluated the effectiveness of the registrant's disclosure
               controls and procedures and presented in this report our
               conclusions about the effectiveness of the disclosure controls
               and procedures, as of the end of the period covered by this
               report based on such evaluation; and

            d) Disclosed in this report any change in the registrant's internal
               control over financial reporting that occurred during the
               registrant's most recent fiscal quarter (the registrant's fourth
               quarter in the case of an annual report) that has materially
               affected, or is reasonably likely to materially affect, the
               registrant's internal control over financial reporting; and

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

            a) All significant deficiencies and material weaknesses in the
               design or operation of internal control over financial reporting
               which are reasonably likely to adversely affect the registrant's
               ability to record, process, summarize and report financial
               information; and

            b) Any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal control over financial reporting.

Date: March 16, 2005

                 /s/ Timothy C. O'Brien
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                          Timothy C. O'Brien
                        Chief Financial Officer
                     (Principal Financial Officer)