This research is an analytical description which positions singing as a tool and supporting material in a danceperformance. In order to limit the problem and focus in more detail on the study material, the sindenan forbedhaya Duradasih was chosen as the material object, specifically in the final performance by students fromthe Dance Department at Institut Seni Indonesia (ISI) Surakarta in 2018. The problem addressed is related tocooperation in the process of interpreting the sindenan for bedhaya Duradasih. In a vocal performance, themain tool for interpreting the material is of course the voice. The way in which the voice is produced is relatedto the technique or method used by each musician, in this case the pesinden (female singer) and penggerong(male singer), in interpreting the material. Therefore, cooperation refers to the way the material is treated in anattempt to realize a vocal performance that is rampak and rempeg. Accuracy in the way breathing is regulatedinfluences the sound of the voice because breathing is the basis of producing sound. Naturally, every person,and more specifically every pesinden and penggerong, has a different way of breathing. This leads to differencesin the way sound is produced in the process of interpreting the material to become a pragmatic reality.In addition, differences in habit for determining preferences in the vocal melody between the pesinden andpenggerong when performing their own roles also creates a problem when performing the sindenan for bedhayaDuradasih in unison. Therefore, in order to realize a vocal performance that is rampak and rempeg a solidprocess of interpretation is required. Every treatment, as a form of interpretation of the material, must beperformed with careful consideration. Departing from this problem, it is known that singing in a dance performance,in particular with the sindenan material for bedhaya Duradasih, involves flexible and open cooperation.The principle mad-sinamadan is a manifestation of the treatment of performance material, bearing in mind thedifferent breathing between the musicians. Mad-sinamadan is performed in an endeavour to realize a vocalperformance that is rampak and rempeg, using a breathing technique in which the singers snatch breathswhile they are singing the vocal melody. The purpose of this is to ensure the continuity and unity of the vocalmelody, because the sindenan for bedhaya Duradasih places more emphasis on the continuity and unity of themelodic line rather than the integrality of the vocal text. Therefore, it may be said that breathing techniqueplays an important role in a vocal performance.