in your case, you are following the Client Flow. so, the Access Token you want is embedded in the redirect uri ( after 'Allow' is clicked ). as documented here: https://v3.developer.constantcontact.com/api_guide/client_flow.html but, i think perhaps you will want to use the Server Flow, which allows for refreshing access tokens via program code. here: https://v3.developer.constantcontact.com/api_guide/server_flow.html i believe both Client and Server flows require hands on interaction for each account your app needs access to. The difference is that the Client flow requires this at each session( well, the token is good for 2 hours? ). The Server flow requires only the initial authorization, then you can refresh the token value(s) as need in code.. Good luck.
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