A privacy-preserving authentication model 
called secret handshake was introduced by Balfanz, Durfee,
Shankar, Smetters, Staddon, and Wong.
It allows two members of a same group to authenticate
themselves secretly to the other
whether they belong to a same group or not,
in the sense that each party reveals his affiliation to the
other only if the other party is also a same group member.
The previous works focus on the models where each participant authenticates
himself as a member of one group.
In this paper, we consider a secret handshake model with multiple groups.
In our model, two users authenticate themselves to the other if and only if
each one's memberships of multiple groups are equal.
We call this model secret handshake with multiple groups.
We also construct its concrete scheme.
Our scheme can easily deal with the change of memberships.
Even if a member is added to a new group, or deleted from the one
that he belongs to,  
it is not necessary to change the memberships for the other
groups that he belongs to.