An interesting costs case has recently been decided by the High Court, R (on the application of Greg Plunkett) v Sefton Metropolitan District Council & Marcel Zachariah (2011), which relates to the quashing of planning permissions. In this case, the claimant applied for judicial review of the grant of the "first planning permission" and maintained this challenge despite the grant of a second planning permission and the existence of a s106 undertaking not to implement the first consent. The Court held (following existing case law) that "very good reasons" had to be put forward to show that the acceptance of such a s106 undertaking would be more appropriate than quashing the first permission. Is anyone aware of any "very good reasons" that would suggest there is no need to quash a permission, or any reason why a planning authority would not want to quash the first permission in such circumstances (surely preferable to a judicial review action and the consequential costs)?