diff --git a/src/database/mod.rs b/src/database/mod.rs
index d3f77c8..2706147 100644
--- a/src/database/mod.rs
+++ b/src/database/mod.rs
@@ -32,7 +32,7 @@ use log::{debug, trace};
 use std::convert::{TryFrom, TryInto};
 use std::fs;
 use std::path::{Path, PathBuf};
-use std::sync::Arc;
+use std::sync::{Arc, Mutex, RwLock};
 use std::time::Duration;
 
 #[derive(Debug)]
@@ -77,6 +77,8 @@ pub struct OpenResult {
 
 pub struct UpEndDatabase {
     pool: DbPool,
+    lock: Arc<RwLock<()>>,
+    transaction_lock: Arc<Mutex<()>>,
     pub vault_path: Arc<PathBuf>,
     pub db_path: Arc<PathBuf>,
 }
@@ -119,6 +121,8 @@ impl UpEndDatabase {
 
         let db = UpEndDatabase {
             pool,
+            lock: Arc::new(RwLock::new(())),
+            transaction_lock: Arc::new(Mutex::new(())),
             vault_path: Arc::new(dirpath.as_ref().canonicalize()?),
             db_path: Arc::new(upend_path),
         };
@@ -164,6 +168,8 @@ impl UpEndDatabase {
     pub fn connection(&self) -> Result<UpEndConnection> {
         Ok(UpEndConnection {
             conn: self.pool.get()?,
+            lock: self.lock.clone(),
+            transaction_lock: self.transaction_lock.clone(),
             vault_path: self.vault_path.clone(),
         })
     }
@@ -171,6 +177,8 @@ impl UpEndDatabase {
 
 pub struct UpEndConnection {
     conn: PooledConnection<ConnectionManager<SqliteConnection>>,
+    transaction_lock: Arc<Mutex<()>>,
+    lock: Arc<RwLock<()>>,
     vault_path: Arc<PathBuf>,
 }
 
@@ -184,7 +192,8 @@ impl UpEndConnection {
         F: FnOnce() -> Result<T, E>,
         E: From<Error>,
     {
-        self.conn.transaction(f)
+        let _lock = self.transaction_lock.lock().unwrap();
+        self.conn.exclusive_transaction(f)
     }
 
     pub fn get_meta<S: AsRef<str>>(&self, key: S) -> Result<String> {
@@ -193,6 +202,8 @@ impl UpEndConnection {
 
         debug!("Querying META:{key}");
 
+        let _lock = self.lock.read().unwrap();
+
         dsl::meta
             .filter(dsl::key.eq(key))
             .load::<models::MetaValue>(&self.conn)?
@@ -210,6 +221,8 @@ impl UpEndConnection {
             Address::Hash(Hash((&file.hash).clone()))
         );
 
+        let _lock = self.lock.write().unwrap();
+
         diesel::insert_into(files::table)
             .values(&file)
             .execute(&self.conn)?;
@@ -226,6 +239,8 @@ impl UpEndConnection {
     pub fn retrieve_file(&self, obj_hash: &Hash) -> Result<Vec<models::OutFile>> {
         use crate::database::inner::schema::files::dsl::*;
 
+        let _lock = self.lock.read().unwrap();
+
         let matches = files
             .filter(valid.eq(true))
             .filter(hash.eq(&obj_hash.0))
@@ -249,6 +264,7 @@ impl UpEndConnection {
 
     pub fn retrieve_all_files(&self) -> Result<Vec<models::File>> {
         use crate::database::inner::schema::files::dsl::*;
+        let _lock = self.lock.read().unwrap();
         let matches = files.load::<models::File>(&self.conn)?;
         Ok(matches)
     }
@@ -258,6 +274,8 @@ impl UpEndConnection {
 
         debug!("Setting file ID {}'s mtime = {:?}", file_id, m_time);
 
+        let _lock = self.lock.write().unwrap();
+
         Ok(diesel::update(files.filter(id.eq(file_id)))
             .set(mtime.eq(m_time))
             .execute(&self.conn)?)
@@ -268,6 +286,8 @@ impl UpEndConnection {
 
         debug!("Setting file ID {} to valid = {}", file_id, is_valid);
 
+        let _lock = self.lock.write().unwrap();
+
         Ok(diesel::update(files.filter(id.eq(file_id)))
             .set(valid.eq(is_valid))
             .execute(&self.conn)?)
@@ -283,6 +303,8 @@ impl UpEndConnection {
     pub fn retrieve_entry(&self, hash: &Hash) -> Result<Option<Entry>> {
         use crate::database::inner::schema::data::dsl::*;
 
+        let _lock = self.lock.read().unwrap();
+
         let entry = data
             .filter(identity.eq(Address::Hash(hash.clone()).encode()?))
             .load::<models::Entry>(&self.conn)?;
@@ -301,6 +323,8 @@ impl UpEndConnection {
     pub fn retrieve_object(&self, object_address: &Address) -> Result<Vec<Entry>> {
         use crate::database::inner::schema::data::dsl::*;
 
+        let _lock = self.lock.read().unwrap();
+
         let primary = data
             .filter(entity.eq(object_address.encode()?))
             .or_filter(value_str.eq(EntryValue::Address(object_address.clone()).to_string()?))
@@ -337,6 +361,8 @@ impl UpEndConnection {
 
         debug!("Deleting {}!", object_address);
 
+        let _lock = self.lock.write().unwrap();
+
         let matches = data
             .filter(identity.eq(object_address.encode()?))
             .or_filter(entity.eq(object_address.encode()?))
@@ -348,6 +374,8 @@ impl UpEndConnection {
     pub fn query(&self, query: Query) -> Result<Vec<Entry>> {
         trace!("Querying: {:?}", query);
 
+        let _lock = self.lock.read().unwrap();
+
         let entries = execute(&self.conn, query)?;
         let entries = entries
             .iter()
@@ -374,6 +402,7 @@ impl UpEndConnection {
     }
 
     fn insert_model_entry(&self, entry: models::Entry) -> Result<usize> {
+        let _lock = self.lock.write().unwrap();
         let result = diesel::insert_into(data::table)
             .values(&entry)
             .execute(&self.conn);
@@ -391,6 +420,8 @@ impl UpEndConnection {
     pub fn get_all_addresses(&self) -> Result<Vec<Address>> {
         use crate::database::inner::schema::data::dsl::*;
 
+        let _lock = self.lock.read().unwrap();
+
         let result = data
             .select(entity)
             .distinct()
@@ -406,6 +437,8 @@ impl UpEndConnection {
     pub fn get_all_attributes(&self) -> Result<Vec<String>> {
         use crate::database::inner::schema::data::dsl::*;
 
+        let _lock = self.lock.read().unwrap();
+
         let result = data
             .select(attribute)
             .distinct()