Via Net Works (VNWI) 10-Q 2005 Q1 Quarterly report

Exhibit 31.1

SECTION 302 CERTIFICATION

I, Ray Walsh, certify that:

1.I have reviewed this quarterly report on Form 10-Q of VIA NET.WORKS, Inc. (“VIA”);

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 cash flows of the registrant as of, and for, the periods presented in this report;

4.VIA’s other certifying officer 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)) for VIA and have:

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

b)evaluated the effectiveness of VIA’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

c)disclosed in this report any change in VIA’s internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) that occurred during VIA’s most recent fiscal quarter  that has materially affected, or is reasonably likely to materially affect, VIA’s internal control over financial reporting.

5.VIA’s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to VIA’s auditors and the audit committee of VIA’s board of directors:

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 VIA’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 VIA’s internal control over financial reporting.

Date: May 20, 2005

/s/ Ray Walsh

Ray Walsh

Chief Executive Officer