Can LINQ Be Used In PowerShell?
Answer : The problem with your code is that PowerShell cannot decide to which specific delegate type the ScriptBlock instance ( { ... } ) should be cast. So it isn't able to choose a type-concrete delegate instantiation for the generic 2nd parameter of the Where method. And it also does't have syntax to specify a generic parameter explicitly. To resolve this problem, you need to cast the ScriptBlock instance to the right delegate type yourself: $data = 0..10 [System.Linq.Enumerable]::Where($data, [Func[object,bool]]{ param($x) $x -gt 5 }) Why does [Func[object, bool]] work, but [Func[int, bool]] does not? Because your $data is [object[]] , not [int[]] , given that PowerShell creates [object[]] arrays by default; you can, however, construct [int[]] instances explicitly: $intdata = [int[]]$data [System.Linq.Enumerable]::Where($intdata, [Func[int,bool]]{ param($x) $x -gt 5 }) To complement PetSerAl's helpful answer with a broader answer to match the qu