Background: The project work (PW) initiative was launched in 2000 by the Ministry of Education, Singapore, to encourage application of knowledge across disciplines, and to develop thinking, communication, collaboration, and metacognitive skills. Although PW has been introduced for a few years, few studies have examined the motivation of students in PW, especially with the use of the recently proposed 2 x 2 achievement goal framework. Aim: To use a cluster analytic approach to identify students' achievement goal profiles at an intra-individual level, and to examine their links to various psychological characteristics and perceived outcomes in PW. Sample: Participants were 491 Secondary 2 students (mean age = 13.78, SD = 0.77) from two government coeducational schools. Method: Cluster analysis was performed to identify distinct subgroups of students with similar achievement goal profiles. One-way MANOVAs, followed by "post hoc" Tukey HSD tests for pairwise comparisons were used to determine whether there was any significant difference amongst clusters in terms of the psychological characteristics and perceived outcomes in PW. Results: Four distinct clusters of students were identified. The cluster with high achievement goals and the cluster with moderately high goals had the most positive psychological characteristics and perceived outcomes. In contrast, the cluster with very low scores for all four achievement goals had the most maladaptive profile. Conclusion: The study provides support for the 2 x 2 achievement goal framework, and demonstrates that multiple goals can operate simultaneously. However, it highlights the need for cross-cultural studies to look into the approach-avoidance dimension in the 2 x 2 achievement goal framework.