1 EXHIBIT 5.1 October 16, 1997 Aspect Telecommunications Corporation 1730 Fox Drive San Jose, CA 95131-2312 REGISTRATION STATEMENT ON FORM S-8 Ladies and Gentlemen: We have examined the Registration Statement on Form S-8 to be filed by you with the Securities and Exchange Commission on or about October 16, 1997 (the "Registration Statement") in connection with the registration under the Securities Act of 1933, as amended effective, of a total of 20,984 shares of your Common Stock (the "Shares") reserved for issuance under the Company's assumed Commerce Soft Inc. 1997 Stock Plan (as amended, effective August 14, 1997) (the "Option Plan"). As your legal counsel, we have examined the proceedings taken and are familiar with the proceedings proposed to be taken by you in connection with the sale and issuance of the Shares under the Option Plan. It is our opinion that, when issued and sold in the manner referred to in the Option Plan and pursuant to the respective agreement which accompanies each grant under the Option Plan, the Shares will be legally and validly issued, fully paid and nonassessable. We consent to the use of this opinion as an exhibit to the Registration Statement and further consent to the use of our name wherever it appears in the Registration Statement and any amendments to it. Sincerely, VENTURE LAW GROUP A Professional Corporation /s/ Venture Law Group