**Exhibit 31.1**

**CERTIFICATION**

     I, S. Scott Crump, certify that:

     1. I have reviewed this annualreport on Form 10-K of Stratasys, Inc. (the “registrant”); 

     2. Based onmy knowledge, this report does not contain any untrue statement of a materialfact or omit to state a material fact necessary to make the statements made, inlight of the circumstances under which such statements were made, not misleadingwith respect to the period covered by this report; 

     3. Based onmy knowledge, the financial statements, and other financial information includedin 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 periodspresented in this report; 

     4. Theregistrant’s other certifying officer and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in Exchange Act Rules13a-15(e) and 15d-15(e)) and internal control over financial reporting (asdefined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant andhave: 

          (a) Designed such disclosure controls and procedures, orcaused such disclosure controls and procedures to be designed under oursupervision, to ensure that material information relating to the registrant,including its consolidated subsidiaries, is made known to us by others withinthose entities, particularly during the period in which this report is beingprepared; 

          (b) Designed such internal control over financial reporting orcaused such internal control over financial reporting to be designed under oursupervision, to provide reasonable assurance regarding the reliability offinancial reporting and the preparation of financial statements for externalpurposes in accordance with generally accepted accounting principles;

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

          (d) Disclosed in this report any change in the registrant’sinternal control over financial reporting that occurred during the registrant’smost recent fiscal quarter (the registrant’s fourth fiscal quarter in the caseof an annual report) that has materially affected, or is reasonably likely tomaterially affect, the registrant’s internal control over financial reporting;and 

     5. Theregistrant’s other certifying officer and I have disclosed, based on our mostrecent evaluation of internal control over financial reporting, to theregistrant’s auditors and the audit committee of the registrant’s board ofdirectors (or persons performing the equivalent functions): 

          (a) All significant deficiencies and material weaknesses inthe design or operation of internal control over financial reporting which arereasonably 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 involvesmanagement or other employees who have a significant role in the registrant’sinternal controls over financial reporting.