Razvoj završnoga l općenito, a u okviru toga razvoj završnoga l u muškom rodu jednine glagolskoga pridjeva radnoga, jedna je u nizu fonoloških pojava čije izoglose presijecaju područje hrvatskoga jezika. Kuda te izoglose prolaze? Podudaraju li se one s tradicionalnom podjelom hrvatskoga jezika na narječja i njihove dijalekte? Nakon napravljenih analiza za štokavsko i čakavsko narječje, navedena se problematika analizira za područje kajkavskoga narječja, na temelju građe za jezične atlase (HJA, OLA), građe prikupljene u drugim istraživanjima te one objavljene u dijelu literature. Problematika se obrađuje geolingvističkom metodologijom, a rezultati analize prikazuju se na jezičnoj karti.In the data available to us there are fifteen types of development of the final l in the l-participle that have been identified in the Kajkavian dialect group in Croatia. The results can be seen on the map. It is probable that in the yet uninvestigated local dialects there could be some more types of development of the final l not recorded here. In the analyzed area are also found the types of development known and confirmed in numerous non-Kajkavian dialects of the Croatian language, among which we can single out the loss of l, usually considered to be specific to the Čakavian dialect group. The isoglosses of the development of the final l do not divide the dialects of the Croatian language in the traditionally accepted way. Research in this field should be continued, but it is already clear that we need to think more about connections than about divisions among dialects