diff --git a/openaq_api/openaq_api/v3/routers/countries.py b/openaq_api/openaq_api/v3/routers/countries.py
index 1a35d6e..7377773 100644
--- a/openaq_api/openaq_api/v3/routers/countries.py
+++ b/openaq_api/openaq_api/v3/routers/countries.py
@@ -2,7 +2,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -75,6 +75,8 @@ async def country_get(
     db: DB = Depends(),
 ):
     response = await fetch_countries(countries, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Country not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/instruments.py b/openaq_api/openaq_api/v3/routers/instruments.py
index 1bad6b0..6ea9940 100644
--- a/openaq_api/openaq_api/v3/routers/instruments.py
+++ b/openaq_api/openaq_api/v3/routers/instruments.py
@@ -2,7 +2,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -90,6 +90,8 @@ async def instrument_get(
     db: DB = Depends(),
 ):
     response = await fetch_instruments(instruments, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Instrument not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/latest.py b/openaq_api/openaq_api/v3/routers/latest.py
index 7693d0b..ff56cf8 100644
--- a/openaq_api/openaq_api/v3/routers/latest.py
+++ b/openaq_api/openaq_api/v3/routers/latest.py
@@ -2,9 +2,11 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
+from openaq_api.v3.routers.locations import LocationPathQuery, fetch_locations
+from openaq_api.v3.routers.parameters import fetch_parameters
 from openaq_api.v3.models.queries import QueryBaseModel, QueryBuilder, Paging
 from openaq_api.v3.models.responses import LatestResponse
 
@@ -87,8 +89,8 @@ class ParametersLatestQueries(ParameterLatestPathQuery, DatetimeMinQuery, Paging
 @router.get(
     "/parameters/{parameters_id}/latest",
     response_model=LatestResponse,
-    summary="Get a owner by ID",
-    description="Provides a owner by owner ID",
+    summary="",
+    description="",
 )
 async def parameters_latest_get(
     parameters_latest: Annotated[
@@ -97,6 +99,10 @@ async def parameters_latest_get(
     db: DB = Depends(),
 ):
     response = await fetch_latest(parameters_latest, db)
+    if len(response.results) == 0:
+        parameters_response = await fetch_parameters(parameters_latest, db)
+        if len(parameters_response.results) == 0:
+            raise HTTPException(status_code=404, detail="Parameter not found")
     return response
 
 
@@ -130,16 +136,22 @@ class LocationsLatestQueries(LocationLatestPathQuery, DatetimeMinQuery, Paging):
 @router.get(
     "/locations/{locations_id}/latest",
     response_model=LatestResponse,
-    summary="Get a owner by ID",
-    description="Provides a owner by owner ID",
+    summary="Get a location's latest measurements",
+    description="Providers a location's latest measurement values",
 )
-async def owner_get(
+async def location_latest_get(
     locations_latest: Annotated[
         LocationsLatestQueries, Depends(LocationsLatestQueries.depends())
     ],
     db: DB = Depends(),
 ):
     response = await fetch_latest(locations_latest, db)
+    if len(response.results) == 0:
+        locations_response = await fetch_locations(
+            LocationPathQuery(locations_id=locations_latest.locations_id), db
+        )
+        if len(locations_response.results) == 0:
+            raise HTTPException(status_code=404, detail="Location not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/licenses.py b/openaq_api/openaq_api/v3/routers/licenses.py
index e2e0014..05759a8 100644
--- a/openaq_api/openaq_api/v3/routers/licenses.py
+++ b/openaq_api/openaq_api/v3/routers/licenses.py
@@ -2,7 +2,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -72,6 +72,8 @@ async def license_get(
     db: DB = Depends(),
 ):
     response = await fetch_licenses(licenses, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="License not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/locations.py b/openaq_api/openaq_api/v3/routers/locations.py
index f00dc99..1dd8995 100644
--- a/openaq_api/openaq_api/v3/routers/locations.py
+++ b/openaq_api/openaq_api/v3/routers/locations.py
@@ -1,7 +1,7 @@
 import logging
 from typing import Annotated
 from enum import StrEnum, auto
-from fastapi import APIRouter, Depends, Path, Query, Request
+from fastapi import APIRouter, Depends, HTTPException, Path, Query, Request
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -98,8 +98,9 @@ async def location_get(
     request: Request,
     db: DB = Depends(),
 ):
-    print("FOO", request.app.state.redis_client)
     response = await fetch_locations(locations, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Location not found")
     return response
 
 
@@ -142,5 +143,6 @@ async def fetch_locations(query, db):
     {query_builder.order_by()}
     {query_builder.pagination()}
     """
+    print("SQL", sql)
     response = await db.fetchPage(sql, query_builder.params())
     return response
diff --git a/openaq_api/openaq_api/v3/routers/manufacturers.py b/openaq_api/openaq_api/v3/routers/manufacturers.py
index fe539c0..e3aa0c1 100644
--- a/openaq_api/openaq_api/v3/routers/manufacturers.py
+++ b/openaq_api/openaq_api/v3/routers/manufacturers.py
@@ -2,7 +2,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -74,6 +74,8 @@ async def manufacturer_get(
     db: DB = Depends(),
 ):
     response = await fetch_manufacturers(manufacturers, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Manufacturer not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/owners.py b/openaq_api/openaq_api/v3/routers/owners.py
index 57ee4d9..96a3880 100644
--- a/openaq_api/openaq_api/v3/routers/owners.py
+++ b/openaq_api/openaq_api/v3/routers/owners.py
@@ -2,7 +2,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -73,6 +73,8 @@ async def owner_get(
     db: DB = Depends(),
 ):
     response = await fetch_owners(owners, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Owner not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/parameters.py b/openaq_api/openaq_api/v3/routers/parameters.py
index 93a5d1e..53aef62 100644
--- a/openaq_api/openaq_api/v3/routers/parameters.py
+++ b/openaq_api/openaq_api/v3/routers/parameters.py
@@ -2,7 +2,7 @@
 from enum import StrEnum, auto
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -149,6 +149,8 @@ async def parameter_get(
     db: DB = Depends(),
 ) -> ParametersResponse:
     response = await fetch_parameters(parameter, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Parameter not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/providers.py b/openaq_api/openaq_api/v3/routers/providers.py
index 981f3c5..ec7d5a7 100644
--- a/openaq_api/openaq_api/v3/routers/providers.py
+++ b/openaq_api/openaq_api/v3/routers/providers.py
@@ -2,7 +2,7 @@
 from typing import Annotated
 from enum import StrEnum, auto
 
-from fastapi import APIRouter, Depends, Path, Query
+from fastapi import APIRouter, Depends, HTTPException, Path, Query
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -101,6 +101,8 @@ async def provider_get(
     db: DB = Depends(),
 ):
     response = await fetch_providers(providers, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Provider not found")
     return response
 
 
diff --git a/openaq_api/openaq_api/v3/routers/sensors.py b/openaq_api/openaq_api/v3/routers/sensors.py
index dc17a27..31c4360 100644
--- a/openaq_api/openaq_api/v3/routers/sensors.py
+++ b/openaq_api/openaq_api/v3/routers/sensors.py
@@ -1,7 +1,7 @@
 import logging
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path
+from fastapi import APIRouter, Depends, HTTPException, Path
 
 from openaq_api.db import DB
 from openaq_api.v3.models.queries import (
@@ -65,7 +65,10 @@ async def sensor_get(
     sensors: Annotated[SensorPathQuery, Depends(SensorPathQuery.depends())],
     db: DB = Depends(),
 ):
-    return await fetch_sensors(sensors, db)
+    response = await fetch_sensors(sensors, db)
+    if len(response.results) == 0:
+        raise HTTPException(status_code=404, detail="Sensor not found")
+    return response
 
 
 async def fetch_sensors(q, db):
diff --git a/openaq_api/tests/fastapi-test.py b/openaq_api/tests/fastapi-test.py
index ce4c307..c1accf4 100644
--- a/openaq_api/tests/fastapi-test.py
+++ b/openaq_api/tests/fastapi-test.py
@@ -43,7 +43,6 @@
     "/v3/providers/62",
     "/v3/sensors/662",
     "/v3/locations/tiles/2/2/1.pbf",
-    "/v3/locations/2178/trends/2",
 ]