diff --git a/src/query/compound.rs b/src/query/compound.rs
index c29e425..11a3681 100644
--- a/src/query/compound.rs
+++ b/src/query/compound.rs
@@ -20,7 +20,9 @@ use serde::{Serialize, Serializer};
 
 use crate::{json::ShouldSkip, units::OneOrMany};
 
-use super::{functions::Function, MinimumShouldMatch, Query, ScoreMode};
+use super::{
+    functions::FilteredFunction, functions::Function, MinimumShouldMatch, Query, ScoreMode,
+};
 
 /// BoostMode
 #[derive(Debug, Copy, Clone)]
@@ -153,7 +155,7 @@ pub struct FunctionScoreQuery {
     query: Option<Query>,
     #[serde(skip_serializing_if = "ShouldSkip::should_skip")]
     boost: Option<f64>,
-    functions: Vec<Function>,
+    functions: Vec<FilteredFunction>,
     #[serde(skip_serializing_if = "ShouldSkip::should_skip")]
     max_boost: Option<f64>,
     #[serde(skip_serializing_if = "ShouldSkip::should_skip")]
@@ -178,12 +180,12 @@ impl FunctionScoreQuery {
     add_field!(with_boost_mode, boost_mode, BoostMode);
     add_field!(with_min_score, min_score, f64);
 
-    pub fn with_functions<A: Into<Vec<Function>>>(mut self, functions: A) -> Self {
+    pub fn with_functions<A: Into<Vec<FilteredFunction>>>(mut self, functions: A) -> Self {
         self.functions = functions.into();
         self
     }
 
-    pub fn with_function<A: Into<Function>>(mut self, function: A) -> Self {
+    pub fn with_function<A: Into<FilteredFunction>>(mut self, function: A) -> Self {
         self.functions = vec![function.into()];
         self
     }
diff --git a/src/query/functions.rs b/src/query/functions.rs
index 11c5ea5..ec05885 100644
--- a/src/query/functions.rs
+++ b/src/query/functions.rs
@@ -25,6 +25,29 @@ use crate::{
     units::{Distance, Duration, JsonVal, Location},
 };
 
+use super::Query;
+
+/// FilteredFunction
+#[derive(Debug, Serialize)]
+pub struct FilteredFunction {
+    #[serde(skip_serializing_if = "ShouldSkip::should_skip")]
+    pub filter: Option<Query>,
+    #[serde(flatten)]
+    pub function: Function,
+}
+
+impl FilteredFunction {
+    pub fn build_filtered_function<A: Into<Option<Query>>>(
+        filter: A,
+        function: Function,
+    ) -> FilteredFunction {
+        FilteredFunction {
+            filter: filter.into(),
+            function,
+        }
+    }
+}
+
 /// Function
 #[derive(Debug, Serialize)]
 pub enum Function {
@@ -239,11 +262,7 @@ impl DecayOptions {
     }
 
     pub fn build<A: Into<String>>(self, field: A) -> Decay {
-        Decay(FieldBased::new(
-            field.into(),
-            self,
-            NoOuter,
-        ))
+        Decay(FieldBased::new(field.into(), self, NoOuter))
     }
 }
 
diff --git a/src/query/mod.rs b/src/query/mod.rs
index 579df61..9104e26 100644
--- a/src/query/mod.rs
+++ b/src/query/mod.rs
@@ -409,7 +409,7 @@ mod tests {
     extern crate serde_json;
 
     use super::full_text::SimpleQueryStringFlags;
-    use super::functions::Function;
+    use super::functions::{FilteredFunction, Function};
     use super::term::TermsQueryLookup;
     use super::{Flags, Query};
 
@@ -449,12 +449,13 @@ mod tests {
     #[test]
     fn test_function_score_query() {
         let function_score_query = Query::build_function_score()
-            .with_function(
-                Function::build_script_score("this_is_a_script")
+            .with_function(FilteredFunction {
+                filter: None,
+                function: Function::build_script_score("this_is_a_script")
                     .with_lang("made_up")
                     .add_param("A", 12)
                     .build(),
-            )
+            })
             .build();
         assert_eq!("{\"function_score\":{\"functions\":[{\"script_score\":{\"lang\":\"made_up\",\"params\":{\"A\":12},\"inline\":\"this_is_a_script\"}}]}}",
                    serde_json::to_string(&function_score_query).unwrap());