There is increasing 'acceptance' that compliance to International Organization for Standardization (ISO) Quality Management Systems is adequate to secure the full benefits of continuous improvement (CI) practice. This appears to detract construction organizations from developing CI practice that can significantly contribute to a culture of CI. This paper proposes that implementation of the Last Planner System (LPS) for improving construction project planning and scheduling (P&S), based on lean construction's TFV theory, can contribute to CI culture within an ISO QMS compliance framework. It is argued that claims regarding lean construction as being amongst one of the many construction improvement 'panaceas' that are non-contextual, generic solutions that are reductionist 'bolt-on' models of change are rather unfounded. In order to substantiate the above argument a CI maturity model was developed based on CI critical success factors based on a Delphi survey, and the CI maturity level of ISO-certified and non-ISO certified construction contracting organizations in the P&S process was compared. 39 ISO-certified and 57 non-ISO certified contractor's CI maturity was analyzed using independent t-test. Although the ISO-certified organizations' CI maturity level was higher, the general maturity level was low, warranting serious consideration for the application of LPS. '