diff --git a/src/core/collection/album.rs b/src/core/collection/album.rs
index 308e901..95dbefb 100644
--- a/src/core/collection/album.rs
+++ b/src/core/collection/album.rs
@@ -138,6 +138,7 @@ pub enum AlbumSecondaryType {
 }
 
 /// The album's ownership status.
+#[derive(Debug)]
 pub enum AlbumOwnership {
     None,
     Owned(TrackFormat),
diff --git a/src/core/musichoard/builder.rs b/src/core/musichoard/builder.rs
index 5ea72ce..a68aac9 100644
--- a/src/core/musichoard/builder.rs
+++ b/src/core/musichoard/builder.rs
@@ -1,6 +1,6 @@
 use crate::core::{
     interface::{database::IDatabase, library::ILibrary},
-    musichoard::{database::IMusicHoardDatabase, Error, MusicHoard, NoDatabase, NoLibrary},
+    musichoard::{database::IMusicHoardDatabase, Error, MusicHoard, NoDatabase, NoLibrary, CollectionFilter},
 };
 
 /// Builder for [`MusicHoard`]. Its purpose is to make it easier to set various combinations of
@@ -62,6 +62,8 @@ impl MusicHoard<NoDatabase, NoLibrary> {
     /// Create a new [`MusicHoard`] without any library or database.
     pub fn empty() -> Self {
         MusicHoard {
+            filter: CollectionFilter::default(),
+            filtered: vec![],
             collection: vec![],
             pre_commit: vec![],
             database: NoDatabase,
@@ -83,6 +85,8 @@ impl<Library: ILibrary> MusicHoard<NoDatabase, Library> {
     /// Create a new [`MusicHoard`] with the provided [`ILibrary`] and no database.
     pub fn library(library: Library) -> Self {
         MusicHoard {
+            filter: CollectionFilter::default(),
+            filtered: vec![],
             collection: vec![],
             pre_commit: vec![],
             database: NoDatabase,
@@ -104,6 +108,8 @@ impl<Database: IDatabase> MusicHoard<Database, NoLibrary> {
     /// Create a new [`MusicHoard`] with the provided [`IDatabase`] and no library.
     pub fn database(database: Database) -> Result<Self, Error> {
         let mut mh = MusicHoard {
+            filter: CollectionFilter::default(),
+            filtered: vec![],
             collection: vec![],
             pre_commit: vec![],
             database,
@@ -127,6 +133,8 @@ impl<Database: IDatabase, Library: ILibrary> MusicHoard<Database, Library> {
     /// Create a new [`MusicHoard`] with the provided [`ILibrary`] and [`IDatabase`].
     pub fn new(database: Database, library: Library) -> Result<Self, Error> {
         let mut mh = MusicHoard {
+            filter: CollectionFilter::default(),
+            filtered: vec![],
             collection: vec![],
             pre_commit: vec![],
             database,
diff --git a/src/core/musichoard/mod.rs b/src/core/musichoard/mod.rs
index f6ba502..8fb7026 100644
--- a/src/core/musichoard/mod.rs
+++ b/src/core/musichoard/mod.rs
@@ -12,11 +12,16 @@ pub use library::IMusicHoardLibrary;
 
 use std::fmt::{self, Display};
 
-use crate::core::collection::Collection;
-
-use crate::core::interface::{
-    database::{LoadError as DatabaseLoadError, SaveError as DatabaseSaveError},
-    library::Error as LibraryError,
+use crate::core::{
+    collection::{
+        album::{AlbumOwnership, AlbumPrimaryType, AlbumSecondaryType},
+        track::TrackFormat,
+        Collection,
+    },
+    interface::{
+        database::{LoadError as DatabaseLoadError, SaveError as DatabaseSaveError},
+        library::Error as LibraryError,
+    },
 };
 
 /// The Music Hoard. It is responsible for pulling information from both the library and the
@@ -24,6 +29,8 @@ use crate::core::interface::{
 // TODO: Split into inner and external/interfaces to facilitate building.
 #[derive(Debug)]
 pub struct MusicHoard<Database, Library> {
+    filter: CollectionFilter,
+    filtered: Collection,
     collection: Collection,
     pre_commit: Collection,
     database: Database,
@@ -32,6 +39,32 @@ pub struct MusicHoard<Database, Library> {
     library_cache: Collection,
 }
 
+/// Filter for a specifying subsets of the entire collection (e.g., for display).
+// Filter is inclusive, not exclusive. To include something in the filtered collection, the filter
+// must select it. It also means that the options below are additive - the more options are set, the
+// more items will be included.
+#[derive(Debug)]
+pub struct CollectionFilter {
+    primary_types: Vec<AlbumPrimaryType>,
+    secondary_types: Vec<AlbumSecondaryType>,
+    include_untyped: bool,
+    ownership: Vec<AlbumOwnership>,
+}
+
+impl Default for CollectionFilter {
+    fn default() -> Self {
+        CollectionFilter {
+            primary_types: vec![AlbumPrimaryType::Ep, AlbumPrimaryType::Album],
+            secondary_types: vec![],
+            include_untyped: true,
+            ownership: vec![
+                AlbumOwnership::Owned(TrackFormat::Mp3),
+                AlbumOwnership::Owned(TrackFormat::Flac),
+            ],
+        }
+    }
+}
+
 /// Phantom type for when a library implementation is not needed.
 #[derive(Debug)]
 pub struct NoLibrary;