Bacterial persistence, which is observed in a broad range of microbial species, is the capacity of a bacterial cell subpopulation called "persisters" to tolerate exposure to normally lethal concentrations of bactericidal antibiotics. This ability, which is not due to antibiotic-resistant mutants, has been implicated in antibiotic treatment failures and may account for latent, chronic, and relapsing infections. Antibiotic tolerant/Persister (AT/P) cells have been notoriously difficult to study due to their low frequency and transient nature. This chapter describes the main methods used to isolate and study Pseudomonas aeruginosa AT/P cells and discusses new technologies that may ease research of P. aeruginosa persisters in the near future.