Studies on student learning of scientific concepts have shown that students often experience various difficulties in understanding basic physics concepts such as vector quantities, as a result of formal and informal learning. The purpose of the present study is to document Grade 11 students' difficulties in understanding vectors and their associated concepts. Specifically, the study tried to find answers to questions about the overall level of difficulty experienced by Grade 11 students about vectors, the nature of these difficulties, and their association with operations, such as scalars, adding vectors graphically, determining vector magnitude and direction, and multiplying vectors by numbers. Altogether, 58 Grade 11 students participated in this study. The study employed a specifically adapted test to assess participants' understanding of vectors in relation to: (1) identifying whether students can distinguish between vectors and scalars, (2) adding vectors graphically, (3) determining the vector magnitude and direction, and (4) multiplying vectors by numbers. The findings suggested that, although most students were able to distinguish between vectors and scalars, they had experienced various difficulties in understanding operations in relation to adding vectors, graphically and mathematically, determining vector magnitudes and directions, and multiplying vectors by numbers. The findings were discussed within the recent UAE educational reform policy.