Purpose - To explore managerial trust in new product development (NPD) projects. Design/methodology/approach - Touches on studies into managerial trust, observing few in the articles in the NPD area. Connects trust, interactional justice, management trust and NPD team performance within a conceptual framework whereby relationship-based antecedents (procedural justice, distributive justice, conflict and transformational leadership) and character-based antecedents (transactional leadership, distributive justice) and team size impacts managerial trust in new product development (NPD) team performance. Examines this, and whether environmental turbulence is a moderator, by testing hypotheses. Surveys Turkish firms (Ankara, Istanbul) using literature-based measures covering 76 items. Analyses data from 127 firms (32% response) concerning 107 NPD projects. Applies factor, correlational, regression and split-group analyses. Findings - Establishes, inter alia, that: procedural justice, distributive justice, and transformational leadership are significantly related to managerial trust; conflict is negatively related; and, managerial trust is significantly related to product success and team learning (under both high and low environmental conditions). States it is only significantly related to speed-to-market under highly turbulent conditions. Research limitations/implications - None stated. Practical implications - Suggests firms work at developing manager-team trust through team involvement in decision-making, generating a favourable justice climate, and developing managers' interpersonal skills. Originality/value - Shows, by a survey of Turkish firms, that trust between manager and project teams impacts team performance and that justice and leadership elements act as trust antecedents.