Table of Contents

Exhibit12.1

CERTIFICATIONS

I, Dan Sten Olsson, certifythat:

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|  | 1.  | I have reviewed this annual report onForm 20-F of Stena AB (publ) (the‘‘Company’’); |

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|  | 2.  | Basedon my knowledge, this report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which suchstatements were made, not misleading with respect to the period coveredby this report; |

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|  | 3.  | Based on my knowledge, thefinancial statements, and other financial information included in thisreport, fairly present in all material respects the financialcondition, results of operations and cash flows of the Company as of,and for, the periods presented in thisreport; |

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|  | 4.  | The Company's other certifyingofficer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules13a-15(e) and 15d-15(e)) for the Company andhave: |

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|  | (a)  | Designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to bedesigned under our supervision, to ensure that material informationrelating to the Company, including its consolidated subsidiaries, ismade known to us by others within those entities, particularly duringthe period in which this report is beingprepared; |

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|  | (b)  | Evaluated the effectiveness of theCompany's disclosure controls and procedures and presented inthis report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by thisreport based on such evaluation; |

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|  | (c)  | Disclosed inthis report any changes in the Company's internal control overfinancial reporting that occurred during the period covered by theannual report that has materially affected, or is reasonably likely tomaterially affect, the Company's internal control over financialreporting; and |

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|  | 5.  | The Company's othercertifying officer and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to theCompany's auditors and the audit committee of the Company'sboard of directors (or persons performing the equivalentfunctions): |

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|  | (a)  | All significant deficiencies andmaterial weaknesses in the design or operation of internal control overfinancial reporting which are reasonably likely to adversely affect theCompany's ability to record, process, summarize and reportfinancial information; and |

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|  | (b)  | Any fraud,whether or not material, that involves management or other employeeswho have a significant role in the Company's internal controlover financial reporting. |

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| Date:June 29, 2006 |  |  | /s/ Dan StenOlsson |
|               |  |  | Name: Dan Sten OlssonTitle: ChiefExecutive Officer |
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