Practice effects often obscure detection of meaningful intraindividual cognitive change in serial assessment. The Trail Making Test and four of its variants (i.e., Trail Making Test of the Delis-Kaplan Executive Functioning System, Comprehensive Trail Making Test, Connections Task, and Planned Connections) were administered to college-aged participants over a 3-week period with 7 days separating each session. Linear growth analysis yielded statistically significant average change in slope across time periods at the p < .05 level for each of the five instruments. The results raise concern about clinical interpretations based upon repeated use of each instrument in serial assessment.