Starting with MEPS in 1979, the four oldest titles set IR's reputation for very high scientific and production values. The journals are hybrids (mix of Subscriber and Open Access). Once the Open Access content of each title reaches sufficient a proportion for the journal to be self-sufficient, it will transition to fully Open Access. 

The high scientific and production values set by IR's venerable Subscription journals carry through to its four younger fully Open Access titles. Some began life as a subscription journal and later “flipped” to fully Open Access; others began as fully Open Access journals. The full content of these journals is freely accessible to all users.