there is provided a method of constructing a listing of e - mail messages , the method comprising : retrieving , by at least one server , information in respect of a plurality of e - mail messages from at least one database in electronic communication with the at least one server , each e - mail message including a header having a plurality of header fields and a body having content ; sending , by the at least one server to a client device via a communications network , instruction to display in one of an e - mail message listing pane or an e - mail message listing window in a graphical user interface of the client device , a listing of e - mails , the listing including in respect of at least some of the e - mail messages listing information including at least some of the header fields ; for a first one of the e - mail messages , one of determining a classification of the first one of the e - mail messages by the at least one server and retrieving from the database a classification of the first one of the e - mail messages by the at least one server , the classification including a sender type and at least one message type ; sending , by the at least one server to the client device via the communications network , instruction to display in the listing information in respect of the first one of the e - mail messages appearing in the listing of e - mail messages a first user - selectable graphical element for causing a first function to be performed in respect of the first one of the e - mail messages , the first function being based , at least in part , on the classification of the first one of the e - mail messages .