Your plan can include team-member seats, letting you invite colleagues into your Bluepic team. Manage them under Settings → Team: invite people by email, and remove them when needed. Every user belongs to exactly one team, and everything a member creates is owned by the team, so templates, campaigns, and assets stay with the team when a member leaves.
Team members can use and export from your private campaigns without consuming credits, and they are who you grant access to in a team campaign.
Free has no seats. Pro includes 10 seats and lets you add more in steps of 5 from Settings → Billing; on Enterprise the team size is part of your contract. Current prices are on the pricing page.