The move represents the beginning of the final stage of the Assembly's £67 million development, which will culminate in the formal opening on 1 March.
The first debates were held in the building's debating chamber yesterday afternoon.
The project has been beset with difficulties historically, the most well-documented being when construction was suspended in 2002 following a very public spat between Rogers and the Assembly government.
However, since the scheme restarted in 2004, when Rogers was reappointed, the construction process has run comparatively smoothly.
The scheme, set in Cardiff Bay, aims to represent the openness of democracy through its architectural form.
In addition, Rogers also emphasises the use of local materials, such as slate, as well as the building's environmental credentials.
The practice believes that the installation of a ground heat source and other 'green' additions will keep the running costs at less than 50 per cent of other comparable designs.
Photographs by Andrew Holt and Richard Bryant at Arcaid