Growing further apart?

Marketing's implicit goal is profit.

Public relations goal is positive perceptions and predispositions.

Marketing's measure of success is the no of sales/revenue generated,PR's measure of success is expressed public opinion or evidence of public support.

Also,a Marketing campaign's effectiveness is measured in months.However,it could takes years,even decades for a brands success to be measured.

Some companies and organizations use only one of these disciplines,others use both.The degree to which they are used vary from organization to organization based on:
Purpose
Size
Organizational history

If an organization is not for profit e.g NGOS,community service organizations,government agencies and it's primary goal was serving the public,PR was the more dominant function because building relationships with it's publics was it's overriding concern.
It's PR unit may be called public information,community relations,community affairs or something else other than PR.
PR coordinated relationships with various publics in order to gain public acceptance and approval of the organization's activities including sales.

However,if an organization was a business and profit was it's main goal.Marketing(possibly sales) was the more dominant function.PR was of secondary importance and used to enhance marketing efforts.Marketing generated sales of goods and services and directly contributed to the organization's profitability.