There are very few, if any, published accounts of practical expe rience with Speaker Verification as a means to provide secure access to telematics services. Yet, there is no reason to expect that Speaker Verification is very different from speech recogni tion, for which many deployed services have shown the need for close and intensive on-line monitoring during the time when the service becomes operational. In this paper we present our expe rience with a monitoring scheme for Speaker Verification dur ing the field test of a financial investment game. Many of the issues that were monitored were suggested by our experience with a semi-operational service, viz. free access to Directory Assistance for visually impaired. A newly developed enrolment procedure, that can flag potentially weak speaker models, is an essential part of the monitoring procedure.