To gauge the variability in expert problem-solving strategies for stoichiometry problems, a set of experts in different career tracks were studied with the cohort including 17 graduate students in chemistry, three college chemistry instructors, and seven college graduates working in the industry. The goal of the study was to determine whether variability would be observed based upon experience and career trajectories. The data were collected using interviews and analyzed qualitatively and quantitatively using the COSINE (Coding System for Investigating Sub-problems and Network) method. Although the method was developed for the analysis of undergraduate problem-solving, it appeared to be effective in examining experts’ problem-solving in chemistry as well. The study revealed similar abilities for succeeding at solving a series of problems, but the strategies were variable for the three cohorts of experts. Specifically, the amount of information used to solve the problems differed across the three cohorts with graduate students focusing more upon each of the specific subproblems within each problem compared to industry chemists utilizing the big-picture approach in lieu of breaking down each problem into respective subproblems. Familiarity with the question types and ability to chunk information were common characteristics observed consistently for the expert participants, which is consistent with existing research.