The invention relates to compositions which include: (a) a polythiophene containing repeating units represented by the following general formula (I), wherein X represents, for example, —CH2—CH(CH2—O—(CH2)4SO3−H+)—; and (b) further polymers, that are different than polythiophene (a), and which contain SO3− M+ or COO−M+ groups. Also disclosed are electroluminescing (EL) arrangements that contain hole-injecting layers which include such compositions.