Organisations that make a relatively large investment in the individuals they hire, including those offering internships and Graduate Programs, may use Assessment Centres to select successful candidates. Assessment Centres are not physical spaces; they are a more elaborate type of application process. (Human Resources) staff from those organisations may be directly involved in assessing candidates or the organisation may have outsourced running of activities to a recruitment agency. A number of selection activities are grouped together and applicants are invited to attend an assessment centre. This may involve a few hours of your time or even a number of days. The process allows employers to assess applicants more holistically against the selection criteria.
See the Careers Toolkit for sample tests to practice.