RDA: Resource Description and Access was first released in 2010. In the North American library cataloging environment, RDA was developed as a replacement for AACR2. This version, now known as the original RDA, is based mostly on the IFLA FRBR conceptual model, defines entities and relationships needed to identify and access information resources, and allows for the transition to the semantic web and linked data environments. Many of its guidelines may seem similar to AACR2. For the majority of its implementation, the original RDA is used in conjunction with MARC. The last update of the original RDA was in April 2017. The new or official RDA was released in December 2020 and is the version currently updated. The current plan is to remove the original RDA from the RDA Toolkit in May 2027.  

The original RDA identifies a number of elements as core elements based on the FRBR assessment of which attributes and relationships are needed to support the general FRBR user tasks (find, identify, select, and obtain). Original RDA guidelines (0.6.1) specify that, at a minimum, a resource description should include all applicable and readily ascertainable core elements. In addition, a description should include all elements that differentiate the resource described from other similar resources.

It is recommended that cataloging agencies establish policies and guidelines for elements not identified as core, or use cataloger's judgment. The Library of Congress (LC) and Program for Cooperative Cataloging (PCC) identified additional elements as core requirements. Since many libraries in the US follow LC-PCC policies and guidelines, applicable policies are incorporated in Chapters 6 & 7.

The original RDA includes a number of alternatives and options, indicated as Alternative, Optional Addition, Optional Omission, or Exception guidelines. Again, in many instances, there is an LC-PCC policy for the adoption of such alternatives and options. Cataloging agencies need to decide on whether or not to use each optional provision by either establishing a local policy or allowing individual catalogers to use their judgment (having users in mind). Agencies using the Library of Congress cataloging data are most likely to conform to LC practice.

The structure of the Original RDA may be indicative of the most common practice to start with the description of the manifestation - the element identifying the manifestation. This may be attributed to the legacy bibliographic data and practice in which the majority of the bibliographic data represented the manifestation. Such records also cover some expression and work data, including relationships to work and expression with the use of access points. Most commonly, data used to identify a work or expression are recorded as authority data. Due to shared (copy) cataloging, most item information is most often not recorded in bibliographic records but in separate "item" records.

Typically, resource description and access information, especially in the MARC environment, are recorded in two types of data records - bibliographic data records and authority data records. This is not necessarily true when using other encoding schemas and structures.

The original RDA defines elements for the recording of identifying attributes for the entity work, expression, manifestation, and item (WEMI). 

Relationships between WEMI entities are recorded in what is traditionally referred to as access points. Controlled access points take a standardized form - in other words - use the established or authorized form of the access point for the work, etc. RDA provides guidelines on which identifying elements and additional information to use for the construction of authorized access points.