Janus Aspen Series
                           Large Cap Growth Portfolio
                            Mid Cap Growth Portfolio
                              Institutional Shares
                                 Service Shares

                       Supplement dated October 19, 2007
                      to Currently Effective Prospectuses

Effective November 1, 2007, the following replaces the corresponding information
in the "INVESTMENT PERSONNEL" section of the Prospectus relating to portfolio
management of Large Cap Growth Portfolio and Mid Cap Growth Portfolio:

  LARGE CAP GROWTH PORTFOLIO

     Co-Portfolio Managers Jonathan D. Coleman and Daniel Riff are responsible
     for the day-to-day management of the Portfolio. Mr. Coleman, as lead
     Portfolio Manager, has the authority to exercise final decision-making on
     the overall portfolio.

     Jonathan D. Coleman, CFA, is Co-Chief Investment Officer of Janus Capital.
     He is Co-Portfolio Manager of Large Cap Growth Portfolio, which he has
     co-managed since November 2007. Mr. Coleman was Portfolio Manager of Mid
     Cap Growth Portfolio from February 2002 to November 2007. Mr. Coleman is
     also Portfolio Manager of other Janus accounts. He joined Janus Capital in
     1994 as a research analyst. Mr. Coleman holds a Bachelor's degree in
     Political Economy and Spanish from Williams College, where he was a member
     of Phi Beta Kappa. As a Fulbright Fellow, he conducted research on economic
     integration in Central America. Mr. Coleman holds the Chartered Financial
     Analyst designation.

     Daniel Riff is Co-Portfolio Manager of Large Cap Growth Portfolio, which he
     has co-managed since November 2007. Mr. Riff is also Portfolio Manager of
     other Janus accounts. Prior to joining Janus Capital in 2003, Mr. Riff was
     a strategy consultant focused on growth and innovation, working in Boston,
     London, and Johannesburg with consumer products, financial services, and
     healthcare firms. Mr. Riff holds a Bachelor's degree (magna cum laude) in
     Economics from Williams College, and a Master of Business Administration
     degree with honors in Finance from The Wharton School at the University of
     Pennsylvania.

  MID CAP GROWTH PORTFOLIO

     Brian Demain, CFA, is Portfolio Manager of Mid Cap Growth Portfolio, which
     he has managed since November 2007. He served as Assistant Portfolio
     Manager of the Portfolio from September 2004 to November 2007. Mr. Demain
     joined Janus Capital in 1999 as a securities analyst. He holds a Bachelor's
     degree in Economics from Princeton University, where he graduated summa cum
     laude and was a recipient of the Daniel L. Rubinfeld '67 Prize in Empirical
     Economics for his senior thesis. Mr. Demain holds the Chartered Financial
     Analyst designation.

David Corkins, the current portfolio manager for Large Cap Growth Portfolio,
will ensure a smooth transition of Large Cap Growth Portfolio through his
departure. Jonathan Coleman, the current portfolio manager for Mid Cap Growth
Portfolio, will work with Brian Demain to ensure a smooth transition of Mid Cap
Growth Portfolio. Effective November 1, 2007 references to David Corkins are
deleted.

                Please retain this Supplement with your records.