For a package foo, how do I find out what other packages depend on foo?

Question

In debian if I have an installed package foo. How can I get a list of all the packages that depend on foo?

Answer 1

apt-cache rdepends <foo> can do this:

$ apt-cache rdepends apt-listchanges
apt-listchanges
Reverse Depends:
  cyrus-common-2.2
  education-common
  cyrus-common-2.2
  apticron
  amavisd-new