Diss has an attractive conservation area at its core, with an exceptional concentration of listed buildings. As well as including the core of the town centre, the conservation area extends around a series of particularly important and distinctive local spaces, including the Parish Fields, and the form and character of Diss is very heavily reliant on the contribution made by these open spaces. A landscape history research carried out by the Norfolk Gardens Trust in 1997 identified a high number of ornamental gardens in Diss, but a lack of small parks, and this was attributed to the industrial nature of the town in the 18th and 19th centuries. As such the public open spaces like the Parish Fields that have survived since the late 19th century are of a particularly high value and have an historical background.

The Parish Fields site is currently identified as an Important Local Open Space in the South Norfolk Local Plan (Development Management Policy DM 4.4: Natural environmental assets - designated and locally important open spaces) and its development for residential use would clearly adversely affect the open character and appearance of the site. Furthermore, the Greater Norwich Local Plan Regulation 18 Consultation Growth Options document dated 20 November 2017 clearly states that "The GNLP will not amend existing adopted Development Management policies for the three districts except in very specific circumstances where limited policy changes may be required".

In addition, the Parish Fields site contributes significantly to the special character and appearance of the conservation area in not just a visual sense, but socially, historically and architecturally; development of the site would clearly be damaging in this context too. As a site with mature trees, some of which are very ancient, were any potentially to be lost it could detrimentally affect the local bat population; the site also provides a safe and tranquil habitat for several other kinds of wildlife, including muntjac deer, pheasants, and grey squirrels as well as many different species of birds, many of which would disappear if development of the site were to be permitted.