Get-AllGlobalAdmins

$clients = Get-MsolPartnerContract
ForEach($client in $clients){
    $role = Get-MsolRole -TenantID $client.TenantID -RoleName "Company Administrator"
    $admins = Get-MsolRoleMember -TenantID $client.TenantID -RoleObjectId $role.ObjectId
    $adminUsers = @()
    ForEach($admin in $admins){
        $adminUser = Get-MsolUser -ObjectId $admin.ObjectId -TenantID $client.TenantID
        $adminUsers += $adminUser
        }
    Write-Output "Client: $($client.Name)"
    $adminUsers | FT DisplayName, UserPrincipalName, AlternateEmailAddresses -AutoSize
}