diff --git a/workshift/models.py b/workshift/models.py
index <HASH>..<HASH> 100644
--- a/workshift/models.py
+++ b/workshift/models.py
@@ -522,6 +522,26 @@ class WorkshiftInstance(models.Model):
 	def pool(self):
 		return self.get_info().pool
 
+	def mark_blown(self, accuser, note=None):
+		'''
+		Marks this workshift instance as blown, saves the object automatically.
+		'''
+		self.blown = True
+		self.closed = True
+		self.save()
+
+		entry = ShiftLogEntry(
+			person=accuser,
+			note=note,
+			entry_type=ShiftLogEntry.BLOWN,
+			)
+		entry.save()
+
+		self.log.add(entry)
+		self.save()
+
+		# TODO: Modify workshifter's profile
+
 	def __init__(self, *args, **kwargs):
 		super(WorkshiftInstance, self).__init__(*args, **kwargs)
 		if (self.weekly_workshift is None and self.info is None) or \
Added method to workshiftinstance to mark a shift as blown