This chapter documents some of the methodological challenges in the use of artificial grammars in second language acquisition (SLA) research. In the three experiments reported here, which followed an artificial grammar learning paradigm, participants were exposed to an artificial language system based on Czech morphology under incidental learning conditions. After several modifications to the design of Experiments 1 and 2, Experiment 3 provided evidence that learners can acquire some knowledge of L2 case marking under incidental learning conditions. Taken together, these three experiments serve to illustrate the challenges that researchers can face when carrying out incidental learning research, in particular the often unreported difficulty in establishing an initial learning effect when piloting a novel, semi-artificial language system.