The terms Employer's Agent and Project Manager are often used interchangeably but they are distinct roles with different contractual responsibilities.
An EA is appointed under design and build contracts to administer the building contract: issuing instructions, reviewing proposals, assessing payments, monitoring progress and certifying practical completion.
A PM provides broader strategic oversight: procurement strategy, design team management, risk management, client reporting and ensuring delivery on time and budget.
An EA is needed with design and build contracts. A PM is valuable on complex projects. On many projects both are needed. On simpler projects one person may fulfil both.
On larger projects the PM manages programme, budget and stakeholders while the EA handles contractual administration. Clear delineation avoids duplication or gaps.
Yes on simpler projects. On complex projects, separating the roles provides better oversight.
Similar but not identical. CA for traditional contracts, EA for design and build.
Not always. For straightforward projects the CA or EA may suffice.
The employer (client). The EA acts in the employer's interest.