The scope of the article is reinterpretation of the question posed by Rodgers and Rodgers, namely, are Public Administration scholarship produced by "disciplined purists" -- Public Administration scholars producing Public Administration research -- or "undisciplined mongrels"? The methodology diverges from previous analysis through examination of doctoral dissertation research classification, rather than faculty output in publications. Concomitantly, Biglan classification of disciplines was used as a framework to determine disciplinary classifications of "undisciplined" or interdisciplinary scholarship. Findings indicate that from 2000 to 2015, there were shifts toward Public Administration as a "purist" discipline. Not only are there changes toward a distinct discipline but also steady declines in outside discipline production of Public Administration doctoral research. The analysis demonstrated a statistically significant increase in categorization of Public Administration scholarship for subjects generally accepted as core issues. Another noted change was dramatic decline for the Doctor of Public Administration degree as the field redefined boundaries.