[LETTERHEAD OF ALSTON & BIRD APPEARS HERE]

                                                                     Exhibit 5.1
                                                                     -----------
                                                                                
                                March __, 1999


LHS Group Inc.
Six Concourse Parkway, Suite 2700
Atlanta, Georgia  30328

  Re:   Registration Statement on Form S-3 (No. 333-__________)

Ladies and Gentlemen:

  We have acted as legal counsel to LHS Group Inc., a Delaware corporation (the
"Company"), and certain stockholders of the Company named in Schedule I hereto
(the "Selling Stockholders") in connection with the filing of the above-
referenced Registration Statement (the "Registration Statement") with the
Securities and Exchange Commission (the "Commission") to register under the
Securities Act of 1933, as amended (the "Act"), 3,735,000 shares of the
Company's Common Stock, par value $.01 per share, including up to 400,000 shares
subject to an over-allotment option (collectively, the "Shares"), for sale by
the Selling Stockholders.  Following the effectiveness of the Registration
Statement, the Selling Stockholders intend to sell the Shares to the public
through the agents (the "Placement Agents") named in Schedule II hereto pursuant
to a placement agency agreement (the "Placement Agreement") by and among the
Company, the Selling Stockholders and the Placement Agents.  This opinion letter
is rendered pursuant to Item 16 of Form S-3 and Item 601(b)(5) of Regulation 
S-K.

  We have examined the Certificate of Incorporation of the Company, as amended,
the Bylaws of the Company, as amended, records of proceedings of the Board of
Directors, or committees thereof, and the stockholders of the Company deemed by
us to be relevant to this opinion letter, the Registration Statement and the
proposed form of Placement Agreement.  We also have examined originals or
copies, certified or otherwise identified to our satisfaction, of such other
corporate records and documents of the Company, such certificates of officers of
the Company, the Selling Stockholders and/or partners thereof and public
officials, and such other records and documents as we have deemed necessary or
appropriate as a basis for the opinions hereinafter expressed.  In such
examination, we have assumed the genuineness of all signatures, the legal
capacity of all natural persons, the authenticity and completeness of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified, conformed, photostatic or facsimile
copies, and the authenticity of the originals of such copies, and we have
assumed all certificates of public officials to have been properly given and to
be accurate.

 
LHS Group Inc.
March  , 1999
Page 2

  As to certain factual matters relevant to this opinion letter, we have relied
upon the representations and warranties contained in the above-referenced
certificates of officers of the Company, the Selling Stockholders and/or
partners thereof and public officials.  Except to the extent expressly set forth
herein, we have made no independent investigations with regard thereto, and,
accordingly, we do not express any opinion as to matters that might have been
disclosed by independent verification.

  Our opinion set forth below is limited to the laws of the State of Delaware,
and we do not express any opinion herein concerning any other laws.

  On the basis of the foregoing, and subject to the limitations set forth
herein, we are of the opinion that, upon due execution and delivery of the
Placement Agreement by the parties thereto and upon delivery of the Shares
against payment therefor as provided in the Placement Agreement, the Shares will
be validly issued, fully paid and nonassessable by the Company.

  We consent to the filing of this opinion letter as an exhibit to the
Registration Statement and to the use of our name under the heading "Legal
Matters" in the Prospectus constituting a part thereof.  In giving such consent,
we do not thereby admit that we are within the category of persons whose consent
is required under Section 7 of the Act or the rules and regulations of the
Commission thereunder.

  This opinion letter is being furnished by us to the Company and the Commission
solely for the benefit of the Company and the Commission in connection with the
Registration Statement and is not to be used, circulated, quoted or otherwise
relied upon by any other person, or by the Company or the Commission for any
other purpose, without our express written consent.  The only opinion rendered
by us consists of those matters set forth in the fifth paragraph hereof, and no
opinion may be implied or inferred beyond those expressly stated.  This opinion
letter is rendered as of the date hereof, and we have no obligation to update
this opinion letter.

                              Sincerely,

                              ALSTON & BIRD LLP


                              By:
                                  ----------------------------
                                  M. Hill Jeffries, a Partner

 
                                  SCHEDULE I
                                        

                         General Atlantic Partners, LLC
                         Dr. Hansjorg Beha
                         Jerry W. Braxton
                         Hartmut Lademacher
                         Jon Limbird
                         Ulf Bohla
                         Erik Froberg

 
                                  SCHEDULE II

                               Deutsche Bank AG

                          SG Cowen International L.P.

                      Bayerischo Hypo-und Vereinsbank AG