We report the use of phosphonium based ionic liquids (ILs) as multifunctional systems for the formation of transition metal ion coordinated polymers. The ILs studied included a tetraalkylated phosphonium cation; [PCnH2n+1]+ and the anions dicyanamide [DCA]- , bis(trifluoromethanesulfonyl)amide [NTf2]-, tosylate [TOS]-, and dodecylbenzenesulfonate [DBSA]-. [DCA]- and other pseudohalide anions such as tricyanomethanide [TCM]- have been shown to co-ordinate to heavy metal centres1. A survey of the literature shows many reports in which [DCA]- (as an alkali salt) has been shown to co-ordinate to these transition metals in various 2-D and 3-D topologies and most notably in structures exhibiting magnetic properties2. We have studied the IL [P6,6,6,14][DCA] as a self-indicating, simultaneous, multianalyte recognition system for heavy metal ions such as Cu2+ and Co2+. When incorporated into a polymer membrane, this system maintains all these attractive features with the added bonus of the IL now being self-plasticizing. A system like this can be viewed as a building block for future chemical sensing platforms; where the system itself is responsive toward an analyte, thereby eliminating the need for a reactive chromophore. Other anions mentioned are considered to be “soft” or non-coordinating. We have used heat to change the chemistry of these anions, resulting in ion coordination to previously solvating anions. These solvating anions have in common a sulfoxide moiety that can co-ordinate to a given heavy metal.3 The formation of these structures has been characterized via UV/Vis, Infrared and Raman Spectroscopy.