This data consists of polygons representing 'Sites with Development Potential' as identified as part of the Shetland Islands Council Local Development Plan, adopted 26th September 2014.
Please see P.15 and P.16 of The Local Development Plan, available online at https://www.shetland.gov.uk/downloads/download/14/local-development-plan-documents-and-maps

Sites with Development Potential:
"Through extensive consultation on the Main Issues Report, Shetland has opted for a
developer-led allocations based system. Between March 2010 and April 2012, the
Call for Sites process invited developers and landowners to submit potential
development sites for consideration. Many landowners have come forward with their
aspirations for development but without detailed plans. Therefore these areas have
been assessed as sites with development potential and will progress to an
allocation status through the Action Programme when more detailed proposals are
established. "

This dataset has been created by Shetland Islands Council using Ordnance Survey data for reference, and has been made available under Ordnance Surveys 'presumption to publish' process as Open Government Licence (OGL) data. https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/

The OGL allows you to:
copy, distribute and transmit the data;

adapt the data; and

exploit the data commercially, whether by sub-licensing it, combining it with other data, or including it in your own product or application.

You are therefore able to use this dataset in any way and for any purpose. 

We simply ask that you acknowledge the copyright and the source of the data by including the following attribution statement: 
Source: Shetland Islands Council Contains OS data  Crown copyright [and database right] (year) 

Liability and Use of this Data:-
Shetland Islands Council makes no guarantees, representations, or warranties of any kind, express or implied, arising by law or otherwise, includingbut not limited to, content, quality, accuracy, completeness, effectiveness, reliability, and fitness for a particular purpose, usefulness, use, or results obtained from this information. Shetland Islands Council assumes no responsibility for damages or other liabilities due to the accuracy, availability, loss of data, use or misuse or the data herein, lost profits, business interruption, loss of business information, or any other pecuniary loss that might arise from the use of this data.