As you search and browse through the directory, you can select members from the directory and add them to "lists". Every member has at least two lists by default: an "IN" list (intended for favorite members) and an "OUT" list (a list of members to avoid). Additional lists can also be created, such as "Good ESL-ENG interpreters in Argentina".
Lists can show availability and your comments about each member. Platinum members can send group messages to entire lists or to selected members of a list, via email or ProZ.com messaging.