A computer-implemented method for visualizing flows through an application, the method comprising: accessing a data store (118, 210) to access data which is obtained from an agent (108, 112, 116) associated with the application, the agent providing the data using instrumentation which is installed in the application; displaying a triage map region on a user interface (122, 500, 520, 525, 530, 540, 550, 555, 556, 560, 570, 580, 590, 600, 600, 620, 630, 631, 640, 650, 660, 670, 680), the triage map region graphically depicting subsystems of the application and dependency relationships between the subsystems, the subsystems being depicted as nodes (320, 321, 322, 324, 326, 328, 330, 336); and characterised in that the dependency relationships are depicted as arrows connecting the nodes, the arrows depicting an order in which the subsystems call one another; receiving a user selection, via the triage map region, of one of the nodes which depicts one of the subsystems; based on the accessed data and in response to the user selection, displaying an auxiliary region of the user interface, the auxiliary region displaying information associated with a transaction instance which invokes the one of the subsystems; receiving a user selection, via the auxiliary region, of the transaction instance; and in response to the user selection of the transaction instance, displaying, via the auxiliary region: a first transaction trace, the first transaction trace being a graph which identifies invoked components (CM 1, CM2, CM4a, CM4b, CM5) of the one of the subsystems in the transaction instance, and calling relationships among the invoked components of the one of the subsystems in the transaction instance; and a second transaction trace, the second transaction trace being a graph which identifies invoked components (CM7, CM8, CM9, CM10) of another of the subsystems which was invoked by the transaction instance, and calling relationships among the invoked components of the another of the subsystems in the transaction instance, the first and second transaction traces being displayed at the same time on a time scale. accessing a data store (118, 210) to access data which is obtained from an agent (108, 112, 116) associated with the application, the agent providing the data using instrumentation which is installed in the application; displaying a triage map region on a user interface (122, 500, 520, 525, 530, 540, 550, 555, 556, 560, 570, 580, 590, 600, 600, 620, 630, 631, 640, 650, 660, 670, 680), the triage map region graphically depicting subsystems of the application and dependency relationships between the subsystems, the subsystems being depicted as nodes (320, 321, 322, 324, 326, 328, 330, 336); and characterised in that the dependency relationships are depicted as arrows connecting the nodes, the arrows depicting an order in which the subsystems call one another; receiving a user selection, via the triage map region, of one of the nodes which depicts one of the subsystems; based on the accessed data and in response to the user selection, displaying an auxiliary region of the user interface, the auxiliary region displaying information associated with a transaction instance which invokes the one of the subsystems; receiving a user selection, via the auxiliary region, of the transaction instance; and in response to the user selection of the transaction instance, displaying, via the auxiliary region: a first transaction trace, the first transaction trace being a graph which identifies invoked components (CM 1, CM2, CM4a, CM4b, CM5) of the one of the subsystems in the transaction instance, and calling relationships among the invoked components of the one of the subsystems in the transaction instance; and a second transaction trace, the second transaction trace being a graph which identifies invoked components (CM7, CM8, CM9, CM10) of another of the subsystems which was invoked by the transaction instance, and calling relationships among the invoked components of the another of the subsystems in the transaction instance, the first and second transaction traces being displayed at the same time on a time scale. a first transaction trace, the first transaction trace being a graph which identifies invoked components (CM 1, CM2, CM4a, CM4b, CM5) of the one of the subsystems in the transaction instance, and calling relationships among the invoked components of the one of the subsystems in the transaction instance; and a second transaction trace, the second transaction trace being a graph which identifies invoked components (CM7, CM8, CM9, CM10) of another of the subsystems which was invoked by the transaction instance, and calling relationships among the invoked components of the another of the subsystems in the transaction instance, the first and second transaction traces being displayed at the same time on a time scale.