diff --git a/Cargo.toml b/Cargo.toml
index c487c623..116430ca 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,6 +34,7 @@ env_logger = "0.10"
 criterion = "0.5"
 fake = "2.4"
 rayon = "1.5"
+serde_json = "1.0"
 
 [[bench]]
 name = "lookup"
diff --git a/src/maxminddb/geoip2.rs b/src/maxminddb/geoip2.rs
index ac89c41c..f2a26949 100644
--- a/src/maxminddb/geoip2.rs
+++ b/src/maxminddb/geoip2.rs
@@ -4,10 +4,15 @@ use serde::{Deserialize, Serialize};
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct Country<'a> {
     #[serde(borrow)]
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub continent: Option<country::Continent<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub country: Option<country::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub registered_country: Option<country::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub represented_country: Option<country::RepresentedCountry<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub traits: Option<country::Traits>,
 }
 
@@ -15,14 +20,23 @@ pub struct Country<'a> {
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct City<'a> {
     #[serde(borrow)]
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub city: Option<city::City<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub continent: Option<city::Continent<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub country: Option<city::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub location: Option<city::Location<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub postal: Option<city::Postal<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub registered_country: Option<city::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub represented_country: Option<city::RepresentedCountry<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub subdivisions: Option<Vec<city::Subdivision<'a>>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub traits: Option<city::Traits>,
 }
 
@@ -30,62 +44,89 @@ pub struct City<'a> {
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct Enterprise<'a> {
     #[serde(borrow)]
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub city: Option<enterprise::City<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub continent: Option<enterprise::Continent<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub country: Option<enterprise::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub location: Option<enterprise::Location<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub postal: Option<enterprise::Postal<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub registered_country: Option<enterprise::Country<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub represented_country: Option<enterprise::RepresentedCountry<'a>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub subdivisions: Option<Vec<enterprise::Subdivision<'a>>>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub traits: Option<enterprise::Traits<'a>>,
 }
 
 /// GeoIP2 ISP record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct Isp<'a> {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub autonomous_system_number: Option<u32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub autonomous_system_organization: Option<&'a str>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub isp: Option<&'a str>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub mobile_country_code: Option<&'a str>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub mobile_network_code: Option<&'a str>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub organization: Option<&'a str>,
 }
 
 /// GeoIP2 Connection-Type record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct ConnectionType<'a> {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub connection_type: Option<&'a str>,
 }
 
 /// GeoIP2 Anonymous Ip record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct AnonymousIp {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_anonymous: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_anonymous_vpn: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_hosting_provider: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_public_proxy: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_residential_proxy: Option<bool>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub is_tor_exit_node: Option<bool>,
 }
 
 /// GeoIP2 DensityIncome record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct DensityIncome {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub average_income: Option<u32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub population_density: Option<u32>,
 }
 
 /// GeoIP2 Domain record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct Domain<'a> {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub domain: Option<&'a str>,
 }
 
 /// GeoIP2 Asn record
 #[derive(Deserialize, Serialize, Clone, Debug)]
 pub struct Asn<'a> {
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub autonomous_system_number: Option<u32>,
+    #[serde(skip_serializing_if = "Option::is_none")]
     pub autonomous_system_organization: Option<&'a str>,
 }
 
@@ -96,33 +137,48 @@ pub mod country {
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Continent<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Country<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_in_european_union: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub iso_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct RepresentedCountry<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_in_european_union: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub iso_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
         #[serde(rename = "type")]
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub representation_type: Option<&'a str>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Traits {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anonymous_proxy: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anycast: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_satellite_provider: Option<bool>,
     }
 }
@@ -136,29 +192,40 @@ pub mod city {
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct City<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
         #[serde(borrow)]
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Location<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub accuracy_radius: Option<u16>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub latitude: Option<f64>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub longitude: Option<f64>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub metro_code: Option<u16>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub time_zone: Option<&'a str>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Postal<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub code: Option<&'a str>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Subdivision<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub iso_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 }
@@ -172,63 +239,100 @@ pub mod enterprise {
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct City<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub confidence: Option<u8>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
         #[serde(borrow)]
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Country<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub confidence: Option<u8>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_in_european_union: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub iso_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Location<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub accuracy_radius: Option<u16>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub latitude: Option<f64>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub longitude: Option<f64>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub metro_code: Option<u16>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub time_zone: Option<&'a str>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Postal<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub confidence: Option<u8>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Subdivision<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub confidence: Option<u8>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub geoname_id: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub iso_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub names: Option<BTreeMap<&'a str, &'a str>>,
     }
 
     #[derive(Deserialize, Serialize, Clone, Debug)]
     pub struct Traits<'a> {
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub autonomous_system_number: Option<u32>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub autonomous_system_organization: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub connection_type: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub domain: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anonymous: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anonymous_proxy: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anonymous_vpn: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_anycast: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_hosting_provider: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub isp: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_public_proxy: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_residential_proxy: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_satellite_provider: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub is_tor_exit_node: Option<bool>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub mobile_country_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub mobile_network_code: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub organization: Option<&'a str>,
+        #[serde(skip_serializing_if = "Option::is_none")]
         pub user_type: Option<&'a str>,
     }
 }
diff --git a/src/maxminddb/reader_test.rs b/src/maxminddb/reader_test.rs
index 4c8bf3b5..38e73932 100644
--- a/src/maxminddb/reader_test.rs
+++ b/src/maxminddb/reader_test.rs
@@ -2,6 +2,7 @@ use std::net::IpAddr;
 use std::str::FromStr;
 
 use serde::Deserialize;
+use serde_json::json;
 
 use super::{MaxMindDBError, Reader};
 
@@ -483,3 +484,23 @@ fn check_ip<T: AsRef<[u8]>>(reader: &Reader<T>, ip_version: usize) {
         }
     }
 }
+
+#[test]
+fn test_json_serialize() {
+    use super::geoip2::City;
+    let _ = env_logger::try_init();
+
+    let filename = "test-data/test-data/GeoIP2-City-Test.mmdb";
+
+    let reader = Reader::open_readfile(filename).unwrap();
+
+    let ip: IpAddr = FromStr::from_str("89.160.20.112").unwrap();
+    let city: City = reader.lookup(ip).unwrap();
+
+    let json_string = json!(city).to_string();
+
+    assert_eq!(
+        json_string,
+        r#"{"city":{"geoname_id":2694762,"names":{"de":"Linköping","en":"Linköping","fr":"Linköping","ja":"リンシェーピング","zh-CN":"林雪平"}},"continent":{"code":"EU","geoname_id":6255148,"names":{"de":"Europa","en":"Europe","es":"Europa","fr":"Europe","ja":"ヨーロッパ","pt-BR":"Europa","ru":"Европа","zh-CN":"欧洲"}},"country":{"geoname_id":2661886,"is_in_european_union":true,"iso_code":"SE","names":{"de":"Schweden","en":"Sweden","es":"Suecia","fr":"Suède","ja":"スウェーデン王国","pt-BR":"Suécia","ru":"Швеция","zh-CN":"瑞典"}},"location":{"accuracy_radius":76,"latitude":58.4167,"longitude":15.6167,"time_zone":"Europe/Stockholm"},"registered_country":{"geoname_id":2921044,"is_in_european_union":true,"iso_code":"DE","names":{"de":"Deutschland","en":"Germany","es":"Alemania","fr":"Allemagne","ja":"ドイツ連邦共和国","pt-BR":"Alemanha","ru":"Германия","zh-CN":"德国"}},"subdivisions":[{"geoname_id":2685867,"iso_code":"E","names":{"en":"Östergötland County","fr":"Comté d'Östergötland"}}]}"#
+    );
+}