This paper focuses on the relationships between exercise scripts and the need to improvise in emergency preparedness exercises. Two relatively large emergency preparedness collaboration exercises are examined (Øvelse Nord 2016 & SCOPE 2017). Our primary observation from these exercises is that they exemplify a common trait: the participants and collaboration partners are governed more by strict manuscripts, where little or nothing is unforeseen. Hence these events are not training innovative practices or improvisation. Path dependency in emergency collaboration exercise can, as shown in the cases, provide both clarity and understanding of the tasks at hand. On the other hand, script dependency in exercises creates an artificial atmosphere where the dynamics of real-time chaos and urgency are left out of the training grounds.