Sustainable Tourism?

I have found way more definitions of sustainability/sustainable tourism than I ever previously anticipated. This has been a problem. I have been trying to boil all of these down into something that makes sense for a few months now. In this space, I'll be listing the strongest definitions or the ones I plan on utilizing, in order for me to get a grasp of what I think is most appropriate for New Bedford. Any commentary on this section would be lovely, since this is turning out to be the more difficult part of the thesis {thus far}.

• "Tourism which is developed & maintained in an area {community, environment} in such a manner & at such a scale that it remains viable over an indefinite period & does not degrade or alter the environment {human or physical} in which it exists to such a degree that it prohibits the successful development & well-being of other activities & processes." {Nelson, J. G., R. Butler and G. Wall. Tourism and Sustainable Development: Monitoring, Planning, Managing. Department of Geography Publication Series No. 37, University of Waterloo, 1993, page 29}