A recent resurgence in support for Matthean Posteriority (Alan Garrow; Rob Macewen) builds on the secure footing of Marcan Priority alongside growing skepticism about Q. Could it be that advocates of what Francis Watson calls the “L/M Theory” have the direction of dependence wrong, and that Matthew knew Luke? The case for Matthean Posteriority refreshes the discussion of the Synoptic Problem by providing a new and interesting challenge, but the case for seeing Luke as a reading of Matthew rather than Matthew as a reading of Luke remains strong: (a) Matthew’s redactional fingerprints repeatedly appear in material he shares with Luke; (b) Luke often shows “fatigue” in his versions of double-tradition material; (c) Luke betrays knowledge of Matthean literary structures; and (d) Matthew fails to include congenial Lucan details on politics, personnel, and geographical context.