Complex decision-making is a prominent aspect of requirements engineering and the need for improved decision support for requirements engineers has been identified by a number of authors. A first step toward better decision support is to understand decision-makers’ complex decision situations. Aspects of decision situations are decision matters, decision-making activities, and decision processes. In this paper we present two requirements engineering decision processes and their decision-making activities and decision matters. These were identified in a case study conducted at Ericsson Microwave Systems. We also discuss the consequences of these for requirements engineering decision support.