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                                                                     EXHIBIT 5.1
 
                                October 28, 1997
 
Aspect Telecommunications Corporation
1730 Fox Drive
San Jose, CA 95131-2312
 
  REGISTRATION STATEMENT ON FORM S-3
 
Ladies and Gentlemen:
 
     We have examined the Registration Statement on Form S-3 to be filed by you
with the Securities and Exchange Commission on or about October 28, 1997 (the
"Registration Statement") in connection with the registration under the
Securities Act of 1933, as amended, of a total of 176,296 shares of your Common
Stock (the "Shares"), to be sold by certain shareholders listed in the
Registration Statement (the "Selling Shareholders"). 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 of the Shares by the
Selling Shareholders in the manner set forth in the Registration Statement in
the section entitled "Plan of Distribution."
 
     It is our opinion that the Shares, when sold by the Selling Shareholders in
the manner referred to in the Registration Statement, 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