The primary objective of this article is to study whether an assessment instrument specifically designed to assess speech motor control on word level productions would be able to add differential diagnostic speech characteristics between people who clutter and people who stutter. It was hypothesized that cluttering is a fluency disorder in which speech motor control on word level is disturbed in high speech rate, resulting in errors in flow of speech and sequencing. An assessment instrument on speech motor coordination on word level was developed and validated. In an elicitation procedure, repetitions of complex multi-syllabic words at a fast speech rate were obtained from 47 dysfluent participants (mean age 24.3; SD 10.25, range 14.2–47.4 yrs) and 327 controls (mean age 25.56 yrs; SD 8.49; age range 14.3–50.1). Speech production was judged on articulatory accuracy, smooth-flow (coarticulation, flow and sequencing) and articulatory rate. Results from people who clutter (PWC) and people who stutter (PWS) were compared to normative data based on control group data. PWC produced significantly more flow and sequencing errors compared to PWS. Further research is needed in order to study speech motor control in spontaneous speech of people who clutter.