Narrative:

Shortly after takeoff (approximately 2 minutes) the flight attendant called. Captain was in discussion with flight attendant over some type door issue. No door lights on overhead panel. I as pilot flying continued flying and talking to ATC as appropriate. Captain informed me he needed to call maintenance over the issue. As we started to climb above 10;000 ft (it was late night and ATC gave us clearance to climb almost immediately); the cabin altitude warning horn sounded. I descended/ leveled at 10;000 ft (we were barely above it). Captain ran QRH checklist; as well as all other appropriate checklists; coordinate with company; flight attendant; made a PA; [and] declared emergency. We returned to [our departure airport] for an uneventful (though overweight) landing.

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Original NASA ASRS Text

Title: B737 First Officer as the pilot flying takes over ATC communication also so the the Captain can discuss a door issue a Flight Attendant. Passing through 10;000 FT the cabin altitude warning horn sounds. An emergency is declared and the flight returns to the departure airport.

Narrative: Shortly after takeoff (approximately 2 minutes) the Flight Attendant called. Captain was in discussion with Flight Attendant over some type door issue. No door lights on overhead panel. I as pilot flying continued flying and talking to ATC as appropriate. Captain informed me he needed to call Maintenance over the issue. As we started to climb above 10;000 FT (it was late night and ATC gave us clearance to climb almost immediately); the cabin altitude warning horn sounded. I descended/ leveled at 10;000 FT (we were barely above it). Captain ran QRH checklist; as well as all other appropriate checklists; coordinate with company; Flight Attendant; made a PA; [and] declared emergency. We returned to [our departure airport] for an uneventful (though overweight) landing.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.