diff --git a/README.md b/README.md
index 7b88d8b..a3d4d4a 100644
--- a/README.md
+++ b/README.md
@@ -11,8 +11,7 @@ Go client for the [Notion API](https://developers.notion.com/reference).
 ### Databases
 
 - [x] [Retrieve a database](database.go)
-- [ ] Query a database
-- [ ] List databases
+- [x] [Query a database](database.go)
 
 ## Pages
 
diff --git a/client.go b/client.go
index a54ccae..501e90e 100644
--- a/client.go
+++ b/client.go
@@ -52,5 +52,9 @@ func (c *Client) newRequest(method, url string, body io.Reader) (*http.Request,
 	req.Header.Set("Notion-Version", apiVersion)
 	req.Header.Set("User-Agent", "go-notion/"+clientVersion)
 
+	if method == http.MethodPost || method == http.MethodPatch {
+		req.Header.Set("Content-Type", "application/json")
+	}
+
 	return req, nil
 }
diff --git a/database.go b/database.go
index 959b5b1..23414e9 100644
--- a/database.go
+++ b/database.go
@@ -1,8 +1,10 @@
 package notion
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
+	"net/http"
 	"time"
 )
 
@@ -16,6 +18,7 @@ type Database struct {
 	Properties     DatabaseProperties `json:"properties"`
 }
 
+// DatabaseProperties is a mapping of properties defined on a database.
 type DatabaseProperties map[string]DatabaseProperty
 
 // Database property metadata types.
@@ -61,6 +64,144 @@ type DatabaseProperty struct {
 	Rollup      *RollupMetadata   `json:"rollup"`
 }
 
+// DatabaseQuery is used for quering a database.
+type DatabaseQuery struct {
+	Filter      DatabaseQueryFilter `json:"filter,omitempty"`
+	Sorts       []DatabaseQuerySort `json:"sorts,omitempty"`
+	StartCursor string              `json:"start_cursor,omitempty"`
+	PageSize    int                 `json:"page_size,omitempty"`
+}
+
+// DatabaseQueryResponse contains the results and pagination data from a query request.
+type DatabaseQueryResponse struct {
+	Results    []Page  `json:"results"`
+	HasMore    bool    `json:"has_more"`
+	NextCursor *string `json:"next_cursor"`
+}
+
+// DatabaseQueryFilter is used to filter database contents.
+// See: https://developers.notion.com/reference/post-database-query#post-database-query-filter
+type DatabaseQueryFilter struct {
+	Property string `json:"property,omitempty"`
+
+	Text        TextDatabaseQueryFilter        `json:"text,omitempty"`
+	Number      NumberDatabaseQueryFilter      `json:"number,omitempty"`
+	Checkbox    CheckboxDatabaseQueryFilter    `json:"checkbox,omitempty"`
+	Select      SelectDatabaseQueryFilter      `json:"select,omitempty"`
+	MultiSelect MultiSelectDatabaseQueryFilter `json:"multi_select,omitempty"`
+	Date        DateDatabaseQueryFilter        `json:"date,omitempty"`
+	People      PeopleDatabaseQueryFilter      `json:"people,omitempty"`
+	Files       FilesDatabaseQueryFilter       `json:"files,omitempty"`
+	Relation    RelationDatabaseQueryFilter    `json:"relation,omitempty"`
+
+	Or  []DatabaseQueryFilter `json:"or,omitempty"`
+	And []DatabaseQueryFilter `json:"and,omitempty"`
+}
+
+type TextDatabaseQueryFilter struct {
+	Equals         string `json:"equals,omitempty"`
+	DoesNotEqual   string `json:"does_not_equal,omitempty"`
+	Contains       string `json:"contains,omitempty"`
+	DoesNotContain string `json:"does_not_contain,omitempty"`
+	StartsWith     string `json:"starts_with,omitempty"`
+	EndsWith       string `json:"ends_with,omitempty"`
+	IsEmpty        bool   `json:"is_empty,omitempty"`
+	IsNotEmpty     bool   `json:"is_not_empty,omitempty"`
+}
+
+type NumberDatabaseQueryFilter struct {
+	Equals               *int `json:"equals,omitempty"`
+	DoesNotEqual         *int `json:"does_not_equal,omitempty"`
+	GreaterThan          *int `json:"greater_than,omitempty"`
+	LessThan             *int `json:"less_than,omitempty"`
+	GreaterThanOrEqualTo *int `json:"greater_than_or_equal_to,omitempty"`
+	LessThanOrEqualTo    *int `json:"less_than_or_equal_to,omitempty"`
+	IsEmpty              bool `json:"is_empty,omitempty"`
+	IsNotEmpty           bool `json:"is_not_empty,omitempty"`
+}
+
+type CheckboxDatabaseQueryFilter struct {
+	Equals       *bool `json:"equals,omitempty"`
+	DoesNotEqual *bool `json:"does_not_equal,omitempty"`
+}
+
+type SelectDatabaseQueryFilter struct {
+	Equals       string `json:"equals,omitempty"`
+	DoesNotEqual string `json:"does_not_equal,omitempty"`
+	IsEmpty      bool   `json:"is_empty,omitempty"`
+	IsNotEmpty   bool   `json:"is_not_empty,omitempty"`
+}
+
+type MultiSelectDatabaseQueryFilter struct {
+	Contains       string `json:"contains,omitempty"`
+	DoesNotContain string `json:"does_not_contain,omitempty"`
+	IsEmpty        bool   `json:"is_empty,omitempty"`
+	IsNotEmpty     bool   `json:"is_not_empty,omitempty"`
+}
+
+type DateDatabaseQueryFilter struct {
+	Equals     time.Time `json:"equals,omitempty"`
+	Before     time.Time `json:"before,omitempty"`
+	After      time.Time `json:"after,omitempty"`
+	OnOrBefore time.Time `json:"on_or_before,omitempty"`
+	OnOrAfter  time.Time `json:"on_or_after,omitempty"`
+	IsEmpty    bool      `json:"is_empty,omitempty"`
+	IsNotEmpty bool      `json:"is_not_empty,omitempty"`
+	PastWeek   *struct{} `json:"past_week,omitempty"`
+	PastMonth  *struct{} `json:"past_month,omitempty"`
+	PastYear   *struct{} `json:"past_year,omitempty"`
+	NextWeek   *struct{} `json:"next_week,omitempty"`
+	NextMonth  *struct{} `json:"next_month,omitempty"`
+	NextYear   *struct{} `json:"next_year,omitempty"`
+}
+
+type PeopleDatabaseQueryFilter struct {
+	Contains       string `json:"contains,omitempty"`
+	DoesNotContain string `json:"does_not_contain,omitempty"`
+	IsEmpty        bool   `json:"is_empty,omitempty"`
+	IsNotEmpty     bool   `json:"is_not_empty,omitempty"`
+}
+
+type FilesDatabaseQueryFilter struct {
+	IsEmpty    bool `json:"is_empty,omitempty"`
+	IsNotEmpty bool `json:"is_not_empty,omitempty"`
+}
+
+type RelationDatabaseQueryFilter struct {
+	Contains       string `json:"contains,omitempty"`
+	DoesNotContain string `json:"does_not_contain,omitempty"`
+	IsEmpty        bool   `json:"is_empty,omitempty"`
+	IsNotEmpty     bool   `json:"is_not_empty,omitempty"`
+}
+
+type FormulaDatabaseQueryFilter struct {
+	Text     TextDatabaseQueryFilter     `json:"text,omitempty"`
+	Checkbox CheckboxDatabaseQueryFilter `json:"checkbox,omitempty"`
+	Number   NumberDatabaseQueryFilter   `json:"number,omitempty"`
+	Date     DateDatabaseQueryFilter     `json:"date,omitempty"`
+}
+
+type DatabaseQuerySort struct {
+	Property  string        `json:"property,omitempty"`
+	Timestamp SortTimestamp `json:"timestamp,omitempty"`
+	Direction SortDirection `json:"direction,omitempty"`
+}
+
+type (
+	SortTimestamp string
+	SortDirection string
+)
+
+const (
+	// Sort timestamp enums.
+	SortTimeStampCreatedTime    SortTimestamp = "created_time"
+	SortTimeStampLastEditedTime SortTimestamp = "last_edited_time"
+
+	// Sort direction enums.
+	SortDirAsc  SortDirection = "ascending"
+	SortDirDesc SortDirection = "descending"
+)
+
 // Metadata returns the underlying property metadata, based on its `type` field.
 // When type is unknown/unmapped or doesn't have additional properies, `nil` is returned.
 func (prop DatabaseProperty) Metadata() interface{} {
@@ -82,8 +223,10 @@ func (prop DatabaseProperty) Metadata() interface{} {
 	}
 }
 
+// FindDatabaseByID fetches a database by ID.
+// See: https://developers.notion.com/reference/get-database
 func (c *Client) FindDatabaseByID(id string) (db Database, err error) {
-	req, err := c.newRequest("GET", "/databases/"+id, nil)
+	req, err := c.newRequest(http.MethodGet, "/databases/"+id, nil)
 	if err != nil {
 		return Database{}, fmt.Errorf("notion: invalid URL: %w", err)
 	}
@@ -94,7 +237,7 @@ func (c *Client) FindDatabaseByID(id string) (db Database, err error) {
 	}
 	defer res.Body.Close()
 
-	if res.StatusCode != 200 {
+	if res.StatusCode != http.StatusOK {
 		return Database{}, fmt.Errorf("notion: failed to find database: %w", parseErrorResponse(res))
 	}
 
@@ -105,3 +248,36 @@ func (c *Client) FindDatabaseByID(id string) (db Database, err error) {
 
 	return db, nil
 }
+
+// QueryDatabase returns database contents, with optional filters, sorts and pagination.
+// See: https://developers.notion.com/reference/post-database-query
+func (c *Client) QueryDatabase(id string, query DatabaseQuery) (result DatabaseQueryResponse, err error) {
+	body := &bytes.Buffer{}
+
+	err = json.NewEncoder(body).Encode(query)
+	if err != nil {
+		return DatabaseQueryResponse{}, fmt.Errorf("notion: failed to encode filter to JSON: %w", err)
+	}
+
+	req, err := c.newRequest(http.MethodPost, fmt.Sprintf("/databases/%v/query", id), body)
+	if err != nil {
+		return DatabaseQueryResponse{}, fmt.Errorf("notion: invalid URL: %w", err)
+	}
+
+	res, err := c.httpClient.Do(req)
+	if err != nil {
+		return DatabaseQueryResponse{}, fmt.Errorf("notion: failed to make HTTP request: %w", err)
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode != http.StatusOK {
+		return DatabaseQueryResponse{}, fmt.Errorf("notion: failed to find database: %w", parseErrorResponse(res))
+	}
+
+	err = json.NewDecoder(res.Body).Decode(&result)
+	if err != nil {
+		return DatabaseQueryResponse{}, fmt.Errorf("notion: failed to parse HTTP response: %w", err)
+	}
+
+	return result, nil
+}
diff --git a/page.go b/page.go
new file mode 100644
index 0000000..9308f5c
--- /dev/null
+++ b/page.go
@@ -0,0 +1,95 @@
+package notion
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+)
+
+// Page is a resource on the Notion platform. Its parent is either a workspace,
+// another page, or a database.
+// See: https://developers.notion.com/reference/page
+type Page struct {
+	ID             string     `json:"id"`
+	CreatedTime    time.Time  `json:"created_time"`
+	LastEditedTime time.Time  `json:"last_edited_time"`
+	Parent         PageParent `json:"parent"`
+	Archived       bool       `json:"archived"`
+
+	// Properties differ between parent type.
+	// See the `UnmarshalJSON` method.
+	Properties interface{} `json:"properties"`
+}
+
+type PageParent struct {
+	Type string `json:"type"`
+
+	PageID     *string `json:"page_id"`
+	DatabaseID *string `json:"database_id"`
+}
+
+// PageProperties are properties of a page whose parent is a page or a workspace.
+type PageProperties struct {
+	Title struct {
+		Title []RichText `json:"title"`
+	} `json:"title"`
+}
+
+// DatabasePageProperties are properties of a page whose parent is a database.
+type DatabasePageProperties map[string]DatabasePageProperty
+
+type DatabasePageProperty struct {
+	DatabaseProperty
+	RichText    []RichText       `json:"rich_text"`
+	Select      *SelectMetadata  `json:"select"`
+	MultiSelect []SelectMetadata `json:"multi_select"`
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+//
+// Pages get a different Properties type based on the parent of the page.
+// If parent type is `workspace` or `page_id`, PageProperties is used. Else if
+// parent type is `database_id`, DatabasePageProperties is used.
+func (p *Page) UnmarshalJSON(b []byte) error {
+	type (
+		PageAlias Page
+		PageDTO   struct {
+			PageAlias
+			Properties json.RawMessage `json:"properties"`
+		}
+	)
+
+	var dto PageDTO
+
+	err := json.Unmarshal(b, &dto)
+	if err != nil {
+		return err
+	}
+
+	page := dto.PageAlias
+
+	switch dto.Parent.Type {
+	case "workspace":
+		fallthrough
+	case "page_id":
+		var props PageProperties
+		err := json.Unmarshal(dto.Properties, &props)
+		if err != nil {
+			return err
+		}
+		page.Properties = props
+	case "database_id":
+		var props DatabasePageProperties
+		err := json.Unmarshal(dto.Properties, &props)
+		if err != nil {
+			return err
+		}
+		page.Properties = props
+	default:
+		return fmt.Errorf("unknown page parent type %q", dto.Parent.Type)
+	}
+
+	*p = Page(page)
+
+	return nil
+}