This paper presents an overview of the author’s doctoral research project, a two-pronged study using both qualitative and quantitative methods. Excerpts of observation material based on video-recorded interactions between mother and infant are presented and discussed, in relation to a psychoanalytic framework with a focus on infantile phantasy. The author also describes the process of developing an assessment scale that attempts to render the rich qualitative data of the observation transcripts as numerical data for comparison with other available quantitative clinical assessments, for the mother-infant pairs studied. The author reflects on some of the challenges of the project and explores possible new directions it could take.