Programs requiring a reciprocal link aren't really directories, a real directory lists everyone who wants to be included. Reciprocal links are NOT free, they do require a time investment to setup. Reciprocal links are also degraded in the search engines, so these link exchange programs are much less effective for helping a site's link popularity than free or paid links. Still, they do work.

Sootle Web Directory
Free categorized and human-edited link directory. Add your international website today. Offers paid and reciprocal link listings. PR6

Linketeria Website Directory
Search useful internet resources for the general public. Websites are listed by popularity and sites that exchange links are clearly labeled. Webmasters submit your site and get reciprocal link promotion instantly!

SlackAlice Global Web Directory
We are listed in SlackAlice, a business oriented reciprocal link program. PR5

ADirect2Z
A searchable directory of websites organised into a wide range of categories. Reciprocal link required. PR4

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