I don't have Account Team Members enabled for my account, so I'm only stabbing in the dark here... 

Bear in mind, this may not be the most efficient code, I'm sure this code can be done much better. I don't even do any try/catch statements

I have not checked whether this code works or not, so you're gonna have to let me know whether it works or not.

trigger AccountTeamMemberTrigger on AccountTeamMember( after insert, after update, after delete ) { List< AccountTeamMember > insertAtm = new List< AccountTeamMember >(); List< AccountTeamMember > updateAtm = new List< AccountTeamMember >(); List< AccountTeamMember > deleteAtm = new List< AccountTeamMember >(); for ( AccountTeamMember atm : Trigger.new ) { // Determine if the Account is a parent List< AccountTeamMembers > atmList = [select AccountId, TeamMemberRole, UserId, AccountAccessLevel from AccountTeamMember where isDeleted = false and Account.ParentId = :atm.AccountId]; List< Account > aList = [select id from Account where Account.ParentId = :atm.AccountId]; // If the list is empty, there are no parent accounts if ( aList.size() > 0 ) { if ( Trigger.isInsert ) { // Assuming child Accounts don't have what the parents do, just add them for ( Account a : aList ) { AccountTeamMember atmInsert = atm.clone( false, true ); atmInsert.AccountId = a.Id; insertAtm.add( atmInsert ); } } if ( Trigger.isUpdate ) { // If the team member UserId matches, update that team member for ( AccountTeamMember atmUpdate : atmList ) { if ( atmUpdate.UserId == atm.UserId ) { atmUpdate.TeamMemberRole = atm.TeamMemberRole; atmUpdate.AccountAccessLevel = atm.AccountAccessLevel; updateAtm.add( atmUpdate ); } } } if ( Trigger.isDelete ) { // If the team member UserId matches, delete that team member for ( AccountTeamMember atmDelete : atmList ) { if ( atmDelete.UserId == atm.UserId ) { atmDelete.TeamMemberRole = atm.TeamMemberRole; atmDelete.AccountAccessLevel = atm.AccountAccessLevel; deleteAtm.add( atmDelete); } } } } } // After all the processing is done, do the required insert/update/deletes if ( insertAtm.size() > 0 ) insert insertAtm; if ( updateAtm.size() > 0 ) update updateAtm; if ( deleteAtm.size() > 0 ) delete deleteAtm; }